AMENDMENT TO
                           TOP AIR MANUFACTURING, INC.
                                STOCK OPTION PLAN


         WHEREAS, Top Air Manufacturing,  Inc. ("Company") as heretofore adopted
the Top Air  Manufacturing,  Inc.'s  Stock  Option Plan (the  "Plan")  effective
November 6, 1992; and

         WHEREAS,  Article VIII of the Plan permits the amendment thereof by the
Board of Directors of the Company (the "Board"); and

         WHEREAS,  the Board has this date authorized the amendment to Section G
of Article IV of the Plan to permit the exercise of options  granted  thereunder
following the termination of the optionee's employment or service as a director,
as the case may be, for reasons other than the  "retirement"  (as defined in the
Plan),  permanent  disability  or death of the  optionee,  for a period of three
months following such termination.

         NOW,  THEREFORE,  the Plan is  hereby  amended  by  deleting  the first
paragraph of Section G of Article IV of the Plan and  substituting the following
in lieu thereof:

                  "G.  Termination  of  Employment  or Cessation of Service as a
         Director.  In the event an individual's  employment with the Company or
         term of service as a director  shall  terminate for reasons other than:
         (i) retirement in accordance with the terms of a retirement plan of the
         Company  ("retirement");  (ii)  permanent  disability  (as  defined  in
         Section 22(e)(3) of the Code); or (iii) death, the individual's Options
         shall  terminate  three months from the date on which such  termination
         occurs, and shall not be exercisable to any extent as of and after such
         time."

         This Amendment shall be effective as of October 1, 1995 with respect to
all options granted under the Plan from and after such date.





         IN WITNESS WHEREOF, the Company has caused the Amendment to be executed
this 1st day of October, 1995.


                                            TOP AIR MANUFACTURING, INC.



                                            By:    /s/ Steven R. Lind
                                            Title: President





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