The 4 dr seats are wider than the coupes and convertibles, so they won't interchange. I believe that the convertible and coupe seats are the same width, and that the seat backs are identical. The rear seat sits more forward in the convertible, vs. the coupe, so there is a difference in the front edge of the seat bottom, where it meets the carpet. However, I think the coupe seat could be modified to work in the convertible. Wayne 66 conv