EXHIBIT 10.3

                                AMENDMENT NO. 5
                                ---------------



          THIS AMENDMENT NO. 5 (this "Agreement") is entered into as of April 
24, 1998 by and among ABC Rail Products Corporation ("Rail"), ABC Deco Inc.
("Deco"), American System Technologies, Inc. ("AST;" AST, Rail and Deco being,
collectively, the "Borrowers"), the financial institutions named on the
signature pages hereto (collectively, the "Lenders") and American National Bank
and Trust Company of Chicago, as agent for the Lenders (the "Agent").

                                    RECITALS
                                    --------

          A.  The Agent, the Lenders and the Borrowers have entered into a 
Second Amended and Restated Loan and Security Agreement dated as of January 31,
1997 (as heretofore amended, supplemented or otherwise modified, the "Loan
Agreement").
 
          B.  The Borrowers have requested that the Agent and the Required 
Lenders agree to amend the Loan Agreement pursuant to the terms and subject to
the conditions hereof.

          C.  The Agent and the Required Lenders are willing to enter into this
Agreement, but only on the terms and subject to the conditions set forth below.

          NOW, THEREFORE, in consideration of the premises set forth above, the
terms and conditions contained herein, and other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties hereto agree as follows:

          1.  Definitions.  Terms defined in the Loan Agreement which are used 
herein shall have the same meaning as are set forth in the Loan Agreement for
such terms unless otherwise defined herein.

          2.  Amendments.  Subject to Section 3 below, the Loan Agreement is 
hereby amended as follows:

          (a)  Section 1.1 is hereby amended as follows:

               (i) The following definition is added in the appropriate
          alphabetical order:

                    "'Wholly-Owned Subsidiary' shall mean any Subsidiary 100% of
               the outstanding capital stock of which is owned by Rail (directly
               or through one or more other Wholly-Owned Subsidiaries)."

 
               (ii) The definition of "Excluded Subsidiary" is hereby deleted.

               (iii) The definition of "Funded Debt" is hereby amended by
     deleting the following: "(other than Excluded Subsidiaries for all purposes
     of this Agreement except Subsection 8.13(D), but including Excluded
     Subsidiaries for purposes of Subsection 8.13(D))."

          (b)  Clause (v) of Subsection 2.4(B)(i) is hereby amended by deleting
"$10,000,000" and inserting in lieu thereof: "$30,000,000."

          (c)  Subsection 3.18 is hereby amended and restated as follows:

               "3.18 Certain Rail Mill Provisions.  Without limiting Subsection
          11.2 of the Agreement, the Borrowers will indemnify the Agent for all
          costs and expenses it may incur in connection with the Mortgagee
          Waiver and Intercreditor Agreement dated as of September 29, 1995
          between Agent and Creditanstalt Corporate Finance, Inc., which costs
          and expenses will be payable on demand. The Purchase Agreement dated
          as of March 27, 1995 by and between Automated Machine Tools, Ltd. and
          Rail is no longer of any force or effect; no purchases of any property
          will be made thereunder; and any property heretofore purchased
          thereunder has been accurately described to the Agent and the Lenders
          in writing.  Rail will cause all personal property and fixtures
          constituting part of the Rail Mill to be maintained separate from all
          other personal property and fixtures of Rail (and its Subsidiaries)
          and readily identifiable as distinct therefrom."

          (d)  Subsection 6.11 is hereby amended by deleting the last sentence
thereof.

          (e)  Subsection 6.12 is hereby amended and restated as follows:

               "6.12  Subsidiaries.  Except as disclosed on Schedule 6.12 and
          except for Subsidiaries acquired in accordance with the terms of
          Subsection 8.3, such Borrower has no Subsidiaries."

          (f)  Clauses A and B of Subsection 7.1 are hereby amended by deleting
the following phrase each time it appears therein: "(other than Excluded
Subsidiaries)."

          (g)  Clause (H) of Subsection 7.1 is hereby amended and restated as
follows:

               "(H) Joint Ventures.  As soon as practicable, and in any event
          within ninety (90) days after the end of each fiscal year of each
          Joint

                                       2

 
          Venture, statements of income, retained earnings and cash flow of each
          Joint Venture for such fiscal year and a balance sheet of such Joint
          Venture as of the end of such fiscal year, all in reasonable detail,
          audited by the Auditors, and certified as accurate by the chief
          financial officer or treasurer of such Person."

          (h)  Clause (viii) of Subsection 8.1 is hereby amended and restated as
follows: "[INTENTIONALLY OMITTED]."

          (i)  Clause (iv) of Subsection 8.2 is hereby amended and restated as
follows:

               "(iv) indebtedness expressly permitted to exist under the terms
     of Subsection 8.4."

          (j)  Clause (v) of Subsection 8.2 is hereby amended and restated as
follows: "[INTENTIONALLY OMITTED]."

          (k)  Subsection 8.3 is hereby amended and restated as follows:

          "8.3  Consolidations, Mergers or Acquisitions.  Such Borrower shall
not, and shall not permit any of its Subsidiaries to, recapitalize, consolidate
with, merge with, or consummate an acquisition (an "Acquisition"), directly or
indirectly, of all or substantially all of the business, assets or properties of
any other Person or any division or line of business of any other Person or
enter into any agreement with respect to any of the foregoing; provided,
however, that (i) subject to the immediately following sentence, Deco may merge
into Rail with Rail being the surviving entity, provided written notice thereof
is promptly given to Agent; (ii) Rail or any Wholly-Owned Subsidiary may
consummate an Acquisition and enter into an agreement to consummate an
Acquisition if (a) the aggregate "Acquisition Price" (as defined below) with
respect to any such Acquisition does not exceed $2,000,000; (b) the aggregate
Acquisition Price with respect to all Acquisitions does not exceed $10,000,000;
(c) no Default or Event of Default exists immediately prior to, or would exist
(determined on a pro forma basis) immediately after, such Acquisition; (d) Rail
has provided written notice to Agent of such Acquisition as soon as practicable
prior to consummation thereof; (e) Agent shall have a valid, first priority
(subject to Subsection 8.1) perfected security interest in all personal property
and fixtures acquired pursuant to such Acquisition and a valid, first priority
(subject to Subsection 8.1) Mortgage on all real property acquired pursuant to
such Acquisition, and all necessary or advisable actions in this regard shall
have been completed at or prior to the time of consummation of such Acquisition
to the reasonable satisfaction of Agent and its counsel (including, without
limitation, satisfaction of the requirements of Subsection 5.2 and 5.3 hereof
and execution and delivery of such security agreements or other documents as
Agent may request); (f) concurrently with consummating such Acquisition, Rail
causes the entity surviving such Acquisition to execute and deliver to Agent a
guaranty, in form and substance acceptable to Agent, of all Liabilities (unless
such surviving entity is Rail or a Subsidiary that has already delivered such a
guaranty to Agent) and (g) Availability (with respect to Rail) immediately
before and immediately after giving effect to such

                                       3

 
Acquisition shall be not less than $10,000,000; and (iii) in addition to any
Acquisition permitted under clause (ii) above, Rail or any Wholly-Owned
Subsidiary may acquire 100% of the stock of, or all or substantially all of the
assets of, SES Co., Inc., a Massachusetts corporation (the "SESCO Acquisition")
on substantially the terms presented by Rail to the Lenders in its "Proposal for
the Acquisition of SES Co., Inc. by American Systems Technologies, Inc." dated
December, 1997 if (a) the aggregate Acquisition Price does not exceed
$11,000,000 at the time of consummating such Acquisition plus common stock, to
be issued by Rail after consummation of the Acquisition upon the occurrence of
certain events, having a fair market value not in excess of $5,700,000 at the
time of issuance , and (b) each of the conditions set forth in clauses (c), (d),
(e), (f) and (g) in the preceding clause (ii) above are satisfied with respect
to the SESCO Acquisition.  In the event Deco merges into Rail as contemplated
by clause (i) above then, effective automatically and concurrently with such
merger, (1) all obligations and liabilities of Deco in connection with this
Agreement (including, without limitation all Liabilities of Deco) shall become
obligations and liabilities of Rail, (2) Deco shall no longer be a "Borrower"
under this Agreement, and (3) the additional modifications to the Agreement
described in Schedule 8.3 hereto shall be effective.  "Acquisition Price" shall
mean, with respect to any Acquisition, the total consideration paid or payable
by Rail or any Subsidiary in connection with such Acquisition including, without
limitation, any and all cash, stock, assumed liabilities, deferred purchase
price amounts, contingent purchase price amounts (based on the assumption that
contingencies giving rise to the maximum amount payable actually occur) and
amounts paid or payable in connection with any non-compete, consulting or
similar arrangements entered into in connection with such Acquisition."

          (l)  Subsection 8.4 is hereby amended and restated as follows:

          "8.4 Investments or Loans.  Such Borrower shall not, and shall not
permit any of its Subsidiaries to, make or permit to exist investments or loans
in or to any other Person, except (i) investments in short-term direct
obligations of the United States Government, (ii) investments in negotiable
certificates of deposit maturing within thirty (30) days from the date of
issuance, issued by any Lender or an affiliate of any Lender or by any other
federally insured bank (provided that any such investments do not exceed the
limit of any such federal insurance) satisfactory to Agent, in its reasonable
discretion, and payable to the order of such Borrower or any of its Subsidiaries
or to bearer and delivered to Agent, (iii) investments in commercial paper
issued by companies organized under the laws of the United States or any state
thereof, maturing in ninety (90) days or less from the date of issuance, which
at the time of acquisition by such Borrower or any such Subsidiary is rated A-
1/P-1 by Standard & Poor's Rating Services (a division of McGraw-Hill Companies,
Inc.) or Moody's Investor Services, Inc., (iv) demand deposits in banks and
similar financial institutions in reasonable amounts necessary to such
Borrower's and its Subsidiaries' operations, (v) advances and reimbursements for
travel and expenses to such Borrower's or its Subsidiaries' officers, directors
or employees in the ordinary course of business and consistent with past
practices, (vi) investments (including debt obligations) received in connection
with the bankruptcy or reorganization of suppliers and customers and in
settlement of delinquent obligations of, and other disputes with, customers and
suppliers arising in the ordinary course of business, (vii) investments existing
on the date hereof by such Borrower in its Subsidiaries and the Joint Ventures
and described on Schedule 8.4, (viii) loans

                                       4

 
made from time to time by Rail to any Wholly-Owned Subsidiary, and loans made
from time to time by any Wholly-Owned Subsidiary to Rail, provided that the
aggregate outstanding principal amount of all such loans at no time exceeds
$2,000,000, (ix) without limiting the foregoing clause (viii), (a) loans made
from time to time by Rail to Deco, provided that (1) the aggregate outstanding
principal amount of all such loans at no time exceeds $7,500,000, and (2) such
loans are evidenced by a promissory note duly pledged to Agent to secure payment
and performance of Rail's Liabilities, (b) loans made from time to time by Rail
to AST, provided that (1) the aggregate outstanding principal amount of all such
loans at no time exceeds $3,000,000, and (2)  such loans are evidenced by a
promissory note duly pledged to Agent to secure payment and performance of
Rail's Liabilities, and (c) the loan made by Rail to its Wholly-Owned
Subsidiary, United Railway Signal Group, in the original principal amount of
$2,050,000 made on or about October 31, 1997, provided that (1) the aggregate
outstanding principal amount of such loan at no time exceeds $2,050,000 minus
the amount of all prepayments and repayments made thereon, and (2)  such loans
are evidenced by a promissory note duly pledged to Agent to secure payment and
performance of Rail's Liabilities, and (x) additional investments not to exceed
$100,000 in the aggregate for all Borrowers and their Subsidiaries at any time
outstanding."

          (m)  Subsection 8.13 (C) is hereby amended and restated as follows:

          "(C) Capital Expenditures.  Incur or permit its Subsidiaries to incur
(i) Capital Expenditures (other than Capital Expenditures financed under
Capitalized Leases):  (a) in an aggregate amount (for Rail and all Subsidiaries)
in excess of $12,000,000 during the period of March 1, 1998 through July 31,
1998; (b) in an aggregate amount (for Rail and all Subsidiaries) in excess of
$25,000,000 during the period of August 1, 1998 through July 31, 1999; provided
that Rail shall be permitted to incur additional Capital Expenditures during
such period in an amount up to $10,000,000 for the sole purpose of funding the
"Permatrack Project" (as such term is defined below); and (c) in an aggregate
amount (for Rail and all Subsidiaries) in excess of $25,000,000 during any
period of four consecutive Fiscal Quarters after July 31, 1999; provided,
however, that in the event Rail and its Subsidiaries make Capital Expenditures
in any period to which clauses (a), (b) and (c) above apply in an amount which
is less than the maximum amount (exclusive of the additional $10,000,000
availability for the Permatrack Project) permitted under each such clause, then
the maximum amount set forth in clauses (b) and (c), as the case may be, with
respect to the following four consecutive Fiscal Quarter period (but only such
following period) shall increase by an amount (the "Rollover Amount") equal to
such difference, or if less, $5,000,000; it being understood that no Rollover
Amount (if any) shall carry over for more than four consecutive Fiscal Quarters;
or (ii) Capital Expenditures, financed under Capitalized Leases, of more than
$2,000,000 in the aggregate for Rail and all Subsidiaries in any period of four
consecutive Fiscal Quarters ending on or after July 31, 1995.  The term
"Permatrack Project" shall mean Rail's proposed line of business involving the
manufacture and sale of heat treated and head-hardened rail to high speed heavy
haul freight railroads as further described in the report entitled "Purchase of
Permatrack Patents" provided by Rail to the Agent by letter dated as of April
24, 1998.

                                       5

 
          (n)  The definition of "EBITDA" set forth in Subsection 8.13 is hereby
amended by deleting "(other than Excluded Subsidiaries)," and by deleting from
clause (iii) thereof "or Excluded Subsidiaries" each time such phrase appears in
such clause (iii).

          (o)  The definition of "Interest Coverage Ratio" set forth in
Subsection 8.13 is hereby amended by deleting the following: "(other than
Excluded Subsidiaries)."

          (p)  The definition of "Interest Expense" set forth in Subsection 8.13
is hereby amended by deleting the following: "(other than Excluded
Subsidiaries)."

          (q)  The definition of "Net Income" set forth in Subsection 8.13 is
hereby amended by deleting the following: "(other than Excluded Subsidiaries for
all purposes of this Agreement except Subsection 8.13(B)(ii), but including
Excluded Subsidiaries for purposes of Subsection 8.13(B)(ii))."

          (r)  Clause (B) of Subsection 8.16 is hereby amended by deleting the
following: "Excluded."

          (s)  Section 7 is hereby amended by adding after Subsection 7.12 the
following:

               "7.13  Appraisal.  On or before July 31, 1998, Rail shall deliver
          to Agent written appraisal reports of the value of all Equipment and
          all real property owned by Rail and all Subsidiaries, in each case
          reasonably satisfactory to Agent in form, scope and methodology and
          prepared by an appraiser reasonably satisfactory to Agent."

          (t)  Paragraph 1 of Schedule 1.1A is hereby amended and restated as
follows:

               "(1) The equipment and fixtures referenced in paragraph 2 of the
          letter from Rail to Agent dated as of April 24, 1998 (and summarized
          on Annex A-1 hereto) that are located at the property described in
          paragraph (2) below."

          (u)  The Loan Agreement is further amended by (1) adding Schedule 8.3
hereto as Schedule 8.3 thereto, and (2) adding Annex A-1 hereto as Annex A-1 to
Schedule 1.1A of the Loan Agreement.

          3.   Conditions.  The terms of Section 2 above shall become effective
as of the date hereof only when each of the following conditions have been
completely satisfied as determined by the Agent in its sole discretion (the date
of such satisfaction being hereinafter referred to as the "Effective Date"):

                                       6

 
               (a)  Documents.  The Agent shall have received each of the
following agreements, instruments and other documents, in each case in form and
substance acceptable to the Agent:

               (i) eight (8) copies of this Agreement duly executed and
     delivered by each of the Borrowers and the Required Lenders;

               (ii) eight (8) copies of a Reaffirmation Agreement duly executed
     and delivered by each of the Borrowers and certain of their affiliates in
     the form of Exhibit A attached hereto;

               (iii) eight (8) copies of a certificate duly executed by the
     corporate secretary of each Borrower as to: (1) the resolutions adopted by
     its Board of Directors (and, if necessary, its shareholders) authorizing
     the execution, delivery and performance of this Agreement and the other
     agreements and instruments contemplated hereby and thereby, (2) the
     incumbency, names and signatures of the officers of such Borrower who are
     duly authorized to execute and deliver the foregoing items, and (3) the
     charter and by-laws of each such Borrower; and

               (iv) such other documents, certificates, agreements, opinions and
     items as the Agent may request in connection herewith.

          (b)  Representations and Warranties; No Default.  As of the Effective
Date, the representations and warranties contained herein and in the Loan
Agreement shall be true and complete, and no Default or Event of Default shall
exist.

          (c)  Proceedings.  All corporate and other proceedings taken or to be 
taken in connection with the transactions contemplated hereby and all documents
incident thereto shall be in form and substance satisfactory to the Agent and
the Required Lenders, as determined in their sole and absolute discretion.

     4.   Representations, Warranties and Agreements of the Borrowers.

          (a)  Each of the Borrowers represents and warrants that: (1) the
execution and delivery by such Borrower of this Agreement and the agreements and
instruments contemplated hereby and the performance of each Borrower's
obligations hereunder and thereunder: (i) are within the corporate powers of
each Borrower; (ii) are duly authorized by the Board of Directors of each
Borrower, and, if necessary, the stockholders of each Borrower; (iii) are not in
contravention of the terms of the charter or by-laws of any Borrower, or of any
contract, instrument, indenture or other agreement or undertaking to which any
Borrower is a party or by which any Borrower or any of its property is bound or
any judgment, decree or order applicable to any Borrower; (iv) do not require
any governmental consent, registration or approval or any filing with or notice
to any

                                       7

 
governmental entity or agency; (v) do not contravene any governmental
restriction binding upon any Borrower; and (vi) will not result in the
imposition of any lien, charge, security interest or encumbrance upon any
property of any Borrower under any indenture, mortgage, deed of trust, loan or
credit agreement or other agreement or instrument to which any Borrower is a
party or by which it or any of its property may be bound or affected; (2) this
Agreement has been duly executed and delivered by each Borrower and constitutes
the legal, valid and binding obligation of each Borrower, enforceable against
each Borrower in accordance with its terms, except as limited by applicable
bankruptcy, reorganization, insolvency or similar laws affecting the enforcement
of creditors' rights generally and except as limited by general principles of
equity; (3) the Loan Agreement, after giving effect hereto, constitutes the
legal, valid and binding obligation of the Borrowers enforceable against the
Borrowers in accordance with its terms, except as enforcement may be limited by
bankruptcy, insolvency, reorganization or other similar laws affecting the
enforcement of creditors' rights generally or by general equitable principles;
and (4) as of the date hereof, and (if different) as of the Effective Date,
there exists no Default or Event of Default.

          (b)  Each of the Borrowers hereby reaffirms all covenants,
representations and warranties made in the Loan Agreement and all other
Financing Agreements. Each of the Borrowers hereby agrees that all covenants,
representations and warranties made in the Loan Agreement and all other
Financing Agreements shall be deemed to have been remade as of the date hereof
and (if different) the Effective Date.

     5.   Reference to the Effect on the Loan Agreement.

          (a)  On and after the Effective Date, (i) each reference in the Loan 
Agreement to "this Agreement," "hereunder," "hereof," "herein," or words of like
import shall mean and be a reference to the Loan Agreement as amended hereby,
and (ii) each reference to the Loan Agreement in all other Financing Agreements
shall mean and be a reference to the Loan Agreement, as amended hereby.

          (b)  Except as specifically amended above, the Loan Agreement, and all
other Financing Agreements and other documents, instruments and agreements
executed and/or delivered in connection therewith, shall remain in full force
and effect, and are hereby ratified and confirmed.

          (c)  The execution, delivery and effectiveness of this Agreement shall
not operate as a waiver of any right, power or remedy of the Agent or the
Lenders, nor constitute a waiver of, or consent to and departure from, any
provision of the Loan Agreement, any other Financing Agreement, or any other
documents, instruments and agreements executed and/or delivered in connection
therewith.

                                       8

 
     6.   Governing Law.  This Agreement shall be governed by and construed in 
accordance with the internal laws (without giving effect to conflicts of law
principles) of the State of Illinois.

     7.   Headings.  Section headings in this Agreement are included herein
for convenience of reference only and shall not constitute a part of this
Agreement for any other purpose.

     8.   Counterparts.  This Agreement may be executed by one or more of the 
parties to this Agreement on any number of separate counterparts and all of said
counterparts taken together shall be deemed to constitute one and the same
instrument. Delivery by any party of an executed counterpart hereof by telecopy
of similar facsimile transmission shall constitute valid and effective delivery
hereof by such party.

               [REMAINDER OF THIS PAGE INTENTIONALLY LEFT BLANK]

                                       9

 
          IN WITNESS WHEREOF, this Agreement has been duly executed as of the
day and year first above written.

                              ABC RAIL PRODUCTS CORPORATION


                              By: /s/ Robert Willmschen Jr.
                                  ___________________________________

                              Title: Chief Financial Officer
                                     ________________________________

                              ABC DECO INC.


                              By: /s/ Robert Willmschen Jr.
                                  ___________________________________

                              Title:__________________________________

                              AMERICAN SYSTEMS TECHNOLOGIES, INC.


                              By: /s/ Robert Willmschen Jr.
                                  ___________________________________

                              Title:__________________________________

                              AMERICAN NATIONAL BANK AND TRUST
                              COMPANY OF CHICAGO, individually and as
                              Agent


                              By: /s/ Donna H. Evans
                                  ___________________________________

                              Title: Vice President
                                     ________________________________

                              PNC BUSINESS CREDIT


                              By: Thomas Fischer
                                  ____________________________________

                              Title: Vice President
                                     _________________________________

 
                              LASALLE NATIONAL BANK


                              By: /s/ Terri Maurer
                                  _____________________________________

                              Title: Vice President
                                     __________________________________

                              NATIONSBANK GEORGIA, N.A.


                              By: /s/ Gaye Stathis
                                  _____________________________________

                                     Vice President
                              Title: __________________________________

                              MELLON BANK, N.A.


                              By: Thomas J. Bugieda
                                  _____________________________________

                                     Assistant Vice President
                              Title: __________________________________

 
                                                                       EXHIBIT A
                                                                       ---------



                                 See Attached.

 
                            REAFFIRMATION AGREEMENT
                            -----------------------


          This Reaffirmation Agreement ("Reaffirmation") is made as of April 24,
1998  by each of the undersigned (collectively, the "Undersigned") in favor of
American National Bank and Trust Company of Chicago, as Agent.


                                    RECITALS
                                    --------


          A.   The Undersigned are parties to one or more Financing Agreements
(as defined in the Loan Agreement referenced below) in connection with that
certain Second Amended and Restated Loan and Security Agreement dated as of
January 31, 1997 (as amended, supplemented or otherwise modified, the "Loan
Agreement"; terms defined in the Loan Agreement have the same meaning herein
unless otherwise defined).

          B.   The Undersigned desire that the Agent and the Lenders enter into
that certain Amendment No. 5 dated as of the date hereof among the Agent, the
Borrowers and the Required Lenders (the "Amendment").

          C.   The Agent and the Required Lenders are willing to enter into the
Amendment only if, among other things, the Undersigned execute and deliver this
Reaffirmation.

          NOW, THEREFORE, in consideration of the facts recited above, to induce
the Agent and the Lenders to enter into the Amendment and for other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the Undersigned each agree as follows:

          1.   The Undersigned each hereby ratify and reaffirm  all of their
respective obligations and liabilities arising under, or relating to, each
Financing Agreement to which it is a party, in each case, after giving effect to
the Amendment, and each of the Undersigned further agree that each Financing
Agreement to which it is a party shall remain in full force and effect in
accordance with its terms, after giving effect to the Amendment.

          2.   Without limiting the foregoing, the term "Loan Agreement" and
each similar reference to the Loan Agreement as used in each Financing Agreement
shall mean and include the Loan Agreement as amended by the Amendment.

          3.   The execution, delivery and effectiveness of the Amendment and
the agreements and instruments contemplated thereby shall not diminish, or
operate as a waiver of, any right, power or remedy of the Agent or any Lender
under any Financing Agreement except to the extent of the waivers expressly set
forth in the Amendment.

          4.   Notice of acceptance hereof is hereby waived by the Undersigned.

 
          IN WITNESS WHEREOF, this Reaffirmation has been duly executed and
delivered as of the date first above written.

                              ABC RAIL PRODUCTS CORPORATION

                                  /s/ D.W. GRINTER
                              By:_________________________________________
                                     CHIEF EXECUTIVE OFFICER
                              Title:______________________________________

                              ABC RAIL PRODUCTS CHINA INVESTMENT
                              CORPORATION

                                  /s/ D.W. GRINTER
                              By:_________________________________________
                                     CHAIRMAN
                              Title:______________________________________

                              ABC RAIL BRAKE SHOE HOLDINGS, INC.

                                  /s/ D.W. GRINTER
                              By:_________________________________________
                                     PRESIDENT
                              Title:______________________________________

                              ABC DECO INC.

                                  /s/ D.W. GRINTER
                              By:_________________________________________
                                     CHAIRMAN
                              Title:______________________________________

                              AMERICAN SYSTEMS TECHNOLOGIES, INC.

                                  /s/ D.W. GRINTER
                              By:_________________________________________
                                     CHAIRMAN
                              Title:______________________________________

                              UNITED RAILWAY SIGNAL GROUP, INC.

                                  /s/ D.W. GRINTER
                              By:_________________________________________
                                     CHIEF EXECUTIVE OFFICER
                              Title:______________________________________

 
                                  ANNEX A- 1                             5/14/98
                                  ----------





- ------------------------------------------------------------------------------------------------
           ITEM                                                       Total P.O.      Actual Pd.
     Machines/Equipment                        Vendor                   Issued         To Date
- ------------------------------------------------------------------------------------------------
                                                                           
- ------------------------------------------------------------------------------------------------
Cranes                                      Illinois Crane            567,913.64      559,910.99
- ------------------------------------------------------------------------------------------------
Rail Car Mover (Diesel)                     Ricci & Co.                98,512.50       98,512.50
- ------------------------------------------------------------------------------------------------
Saw-Drill for Rail & D-Bar (Saw #1)         Centro Metalcut         1,450,000.00    1,354,264.50
- ------------------------------------------------------------------------------------------------
Metalcut IIIP H.S.S. Saw (Saw #2)           Centro Matalcut           991,975.39      805,736.00
- ------------------------------------------------------------------------------------------------
Bender                                      Williams White            214,350.00      171,480.00
- ------------------------------------------------------------------------------------------------
D-Bar Mill                                  Versamill                 449,750.00      404,775.00
- ------------------------------------------------------------------------------------------------
D-Bar Fixtures-Magnetic chucks              Tecnomagnette              76,200.00       75,700.00
- ------------------------------------------------------------------------------------------------
SNK Gantry Milling Machine 90' for rails    Gulf Components         1,884,000.00    1,884,000.00
- ------------------------------------------------------------------------------------------------
SNK Rebuild & Modify (for rails)            MTR Ravensburg          2,455,537.00    2,446,857.90
- ------------------------------------------------------------------------------------------------
100 HP Heads                                Devlieg/Futuremill        804,448.00      710,400.00
- ------------------------------------------------------------------------------------------------
SNK Fixtures-Magnetic Chucks                Tecnomagnette             440,000.00      418,000.00
- ------------------------------------------------------------------------------------------------
Other
  Roofing Solutions                                                   514,897.00      514,897.00
- ------------------------------------------------------------------------------------------------
  Kirivan (heating)                                                   105,000.00      105,000.00
- ------------------------------------------------------------------------------------------------
  Turner Machinery (gantry)                                            95,000.00       95,000.00
- ------------------------------------------------------------------------------------------------
- ------------------------------------------------------------------------------------------------
Total                                                              10,147,583.53    9,644,533.89
- ------------------------------------------------------------------------------------------------


 
                                  SCHEDULE 8.3
                                  ------------

          Provided below are certain amendments to the Agreement that pursuant
to Subsection 8.3 thereof will automatically become effective upon the merger
(if any) of Deco with and into Rail as contemplated by Subsection 8.3 thereof.

          1.   The definition of "Borrower" set forth in Subsection 1.1 is
amended and restated as follows: "Borrower" shall mean each of Rail and AST,
individually, and "Borrowers" shall mean "Rail and AST, collectively."

          2.   The definition of "Inventory Sublimit" set forth in Subsection 
1.1 is amended and restated as follows: "Inventory Sublimit" shall mean, with
respect to Rail, the "Rail Inventory Sublimit" (as defined in Subsection 2.4
hereof).

          3.   Subsection 2.4 (B)(ii) is amended and restated as follows:  
"[INTENTIONALLY OMITTED]."

          4.   Subsection 5.1 is amended by deleting the words "and Deco" and 
inserting in lieu thereof: "and AST."

          5.   Subsection 8.4 is amended by deleting clause (ix)(a) and 
inserting in lieu thereof: "[INTENTIONALLY OMITTED]."

          6.   Subsection 9.1(D), Subsection 9.1(M) and Subsection 11.6(C) are 
each amended by deleting the words "Deco and."

          7.   Subsection 11.17(iv) is amended by deleting the words "Deco or."

          8.   Schedules 6.1, 6.5, 6.7, 6.8, 6.12, 6.16 are each amended by
deleting the references to "Deco" therein and the information set forth therein
that specifically and exclusively applies to Deco.