I just found another difference the other day about 64.5/65. My 64.5 buckets need to be recovered bad, and I just picked up another set with no tears that came out of a 65 for a good price, that I'll use till I recover my originals. I was planning to use my tracks on the seats as they where in better condition, but noticed that the 64.5 tracks would not bolt up to the bottom of the 65 seats. The bolt pattern is about a half inch more narrow on the early seats. Oh, and my car is a late July 64 car and has the adjustable seat on the passenger side.

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