rear seat fitment

I'm thinking you might have sorted this out for yourself by now but I'm new here so I think can get away with resurrecting this for you since nobody else has piped up! I believe all A-Bodies are the same basic seats just with different covers between models and years. As an example the back seat bottom in my 67 Barracuda FB was in pretty bad shape so I tried the bottom from a 73 Dart Sport, it popped right in hooking up to the "catches" perfectly. It even filled in the gaps at the sides against the wheelhouses nicer than the original. Fold-down and non-fold-down are obviously another story.

For a more direct approach Legendary shows non-fold-down rear seats under one part number for each color as "72/73 DART/DART SPORT/DEMON/DUSTER"

Hope this helps your project!