EXHIBIT 10.63

 
                            SUPPLEMENTAL INDENTURE


          SUPPLEMENTAL INDENTURE (this "Supplemental Indenture"), dated as of
December, 1, 1997 between Duo-Form of Michigan, Inc. (the "New Subsidiary
Guarantor"), a Subsidiary of Kevco, Inc., a Texas corporation (the "Company"),
and United States Trust Company of New York, as trustee under the indenture
referred to below (the "Trustee").  Capitalized terms used herein and not
defined herein shall have the meanings ascribed to them in the Indenture (as
defined below).

                             W I T N E S S E T H:

          WHEREAS, the Company has heretofore executed and delivered to the
Trustee an Indenture (the "Indenture"), dated as of December 1, 1997, providing
for the issuance of an aggregate principal amount of $105,000,000 of 10 3/8%
Senior Subordinated Notes due 2007 (the "Notes");

          WHEREAS, Section 10.09 of the Indenture provides that under certain
circumstances the Company may cause certain of its Subsidiaries to execute and
deliver to the Trustee a supplemental indenture pursuant to which such
Subsidiaries shall unconditionally Guarantee all of the Company's obligations
under the Indenture and the Notes pursuant to a Subsidiary Guarantee on the
terms and conditions set forth herein; and

          WHEREAS, pursuant to Section 9.01 of the Indenture, the Trustee is
authorized to execute and deliver this Supplemental Indenture.

          NOW, THEREFORE, in consideration of the foregoing and for other good
and valuable consideration, the receipt of which is hereby acknowledged, the New
Subsidiary Guarantor and the Trustee mutually covenant and agree for the equal
and ratable benefit of the Holders of Notes as follows:

          1.  CAPITALIZED TERMS.  Capitalized terms used herein without
definition shall have the meanings ascribed to them in the Indenture.

          2.  INDENTURE PROVISION PURSUANT TO WHICH SUBSIDIARY GUARANTEE IS
GIVEN. This Supplemental Indenture is being executed and delivered pursuant to
Section 10.09 of the Indenture.

          3.  AGREEMENT TO GUARANTEE.  The New Subsidiary Guarantor hereby
agrees, jointly and severally with all other Subsidiary Guarantors, to
irrevocably and unconditionally guarantees that (i) the principal of, premium,
if any, interest and Liquidated Damages, if any, on the Notes shall be duly and
punctually paid in full when due, whether at stated maturity, by acceleration,
call for redemption, upon a Change of Control Offer, upon an Asset Sale Offer,
pursuant to the Escrow Agreement or otherwise, and interest on overdue
principal, premium, if any, (to the extent

 
permitted by law) interest on any interest, if any, and Liquidated Damages, if
any, on the Notes and all other obligations of the Company to Holders of Notes
or the Trustee under the Indenture or under the Notes (including fees, expenses
or otherwise) will be promptly paid in full or performed, all in accordance with
the terms thereof, (ii) in case of any extension of time of payment or renewal
of any Notes or any of such other obligations, the same shall be promptly paid
in full when due or performed in accordance with the terms of the extension or
renewal, whether at stated maturity, by acceleration, call for redemption, upon
a Change of Control Offer, upon an Asset Sale Offer, pursuant to the Escrow
Agreement or otherwise and (iii) the prompt payment of any and all costs and
expenses (including reasonable attorneys' fees) incurred by the Trustee or any
Holder of Notes in enforcing any rights under the Indenture or under the Notes,
on the terms and subject to the conditions set forth in Article 10 of the
Indenture and to be bound by all other applicable provisions of the Indenture
applicable to a Restricted Subsidiary and/or Subsidiary Guarantor thereunder.

          4.      EXECUTION AND DELIVERY OF SUBSIDIARY GUARANTEES

          (a) To evidence its Subsidiary Guarantee, the New Subsidiary Guarantor
hereby agrees that a notation of such Subsidiary Guarantee substantially in the
form set forth in Exhibit A to the Indenture shall be endorsed by an officer of
such New Subsidiary Guarantor on each Note authenticated and delivered by the
Trustee after the date hereof.

          (b) Notwithstanding the foregoing, the New Subsidiary Guarantor hereby
agrees that its Subsidiary Guarantee shall remain in full force and effect
notwithstanding any failure to endorse on each Note a notation of such
Subsidiary Guarantee.

          (c) If an officer whose signature is on this Supplemental Indenture or
on the notation of the Subsidiary Guaranty no longer holds that office at the
time the Trustee authenticates the Note on which a Subsidiary Guarantee is
endorsed, the Subsidiary Guarantee shall be valid nevertheless.

          (d) The New Subsidiary Guarantor hereby agrees that its Subsidiary
Guarantee shall be unconditional, regardless of the validity, regularity or
enforceability of the Notes or the Indenture, the absence of any action to
enforce the same, any waiver or consent by any Holder of Notes with respect to
any provisions hereof or thereof, the recovery of any judgement against the
Company, any action to enforce the same or any other circumstance which might
otherwise constitute a legal or equitable discharge or defense of a guarantor.

          (e) The New Subsidiary Guarantor covenants (to the extent that it may
lawfully do so) that it will not at any time insist upon, or plead, or in any
manner whatsoever claim or take the benefit or advantage of, any stay, extension
or usury law wherever enacted, now or at any time hereafter in force, which may
affect the covenants or the performance of the Indenture or its Subsidiary
Guarantee; and the New Subsidiary Guarantor (to the extent that it may lawfully
do so) hereby expressly waives all benefit or advantage of any such law, and
covenants that it will not

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hinder, delay or impede the execution of any power granted to the Trustee, but
will suffer and permit the execution of every such power as though no such law
had been enacted.

          5.  NO RECOURSE AGAINST OTHERS.  No director, officer, employee,
incorporator or stockholder of any Subsidiary Guarantor, as such, shall have any
liability for any obligations of the Company or any Subsidiary Guarantor under
the Notes, any Subsidiary Guarantees, the Indenture or this Supplemental
Indenture or for any claim based on, in respect of, or by reason of, such
obligations or their creation.  Each Holder of Notes by accepting a Note waives
and releases all such liability.  The waiver and release are part of the
consideration for issuance of the Notes and the Subsidiary Guarantees.

          6.  NEW YORK LAW TO GOVERN.  The internal law of the State of New York
shall govern and be used to construe this Supplemental Indenture.

          7.  COUNTERPARTS.  The parties may sign any number of copies of this
Supplemental Indenture.  Each signed copy shall be an original, but all of them
together represent the same agreement.

          8.  EFFECT OF HEADINGS.  The Section headings herein are for
convenience only and shall not effect the construction hereof.

          9.  THE TRUSTEE.  The Trustee shall not be responsible in any manner
whatsoever for or in respect of the validity or sufficiency of this Supplemental
Indenture or for or in respect of the correctness of the recitals of fact
contained herein, all of which recitals are made solely by the New Subsidiary
Guarantor.

          IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed and attested, all as of the date first above
written.


Dated:  December 1, 1997                DUO-FORM OF MICHIGAN, INC.


                                        By:     /s/  ELLIS L. MCKINLEY, JR.  
                                           -------------------------------------
                                        Name:        Ellis L. McKinley, Jr.
                                             -----------------------------------
                                        Title:       Vice President
                                              ----------------------------------

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Dated:  December 1, 1997                UNITED STATES TRUST COMPANY OF
                                               NEW YORK, as Trustee


                                        By:     /s/ G. E. GANEY
                                           -------------------------------------
                                        Name:       Gerard E. Ganey
                                             -----------------------------------
                                        Title:      Senior Vice President
                                              ----------------------------------


                

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