1964 Dart seats
64-66 should fit. I think that cars came with holes and pads for either bucket or bench, not both. There was a post a few months ago in Early-A's asking that question, w/ photos and answers.
In my 64 & 65, I am installing more modern seats from a Mustang Cobra Conv. & Sebring Conv. That is to get shoulder belts & head restraint, plus much cheaper than just getting new vinyl covers for my bucket seats. The electric adjusts are nice too.