I have a good running 1994 Force 50. I found an ad where they are selling a running (but roughly) 1991 Force 50 as well as a 1990 parts motor. They are asking $300 for both motors. Electrical components are totally different, and when I compare the engine parts (i.e.. motor block and cylinder head) the part numbers are not the same but they look the same in the diagram. Would anyone know how much of the major parts would be interchangeable? Thanks.