I know that Supreme hdtp and Supreme convertible rear seats are different sizes, but what about rear seats for:

2 dr "fastback"
2 dr post
4 dr

Thanks!
Steve

 

4 door rear seat is a totally different (corners of the seat bottom are rounded off for passengers to get in/out)

Fast back & post cars would be the same rear seat for 70-72 i beleive
(earlier years there was a base level trim option that had a wider rear seat w/o the nice arm rests, but those were really rare)

And as you noted convertibles have a narrower rear seat do to the wide armrests covering the top hydraulics.

 

Thanks!