Mid 70 Bucket TRACKS !!!
F-body floors are different than others, so if you're going for an exact fit, it's F-body (and maybe M-body) only. I've tried both J-body and late B-body buckets seat tracks in a '77 F-body, and the J-bodies are too different to use. The late B-body tracks are close, but one is different since F-bodies have the floor hump to clear the catalytic converter.