71-72 seats. Frames the same??

This is just a guess to your question, so keep that in mind.

71 was a split year with the seat button release. Early 71 was the same long button style as the 70 seats w/ the potmetal seat sides which separated from the seats. Late 71 and 72 had an integrated seat button that was chrome and shorter.

With that being said, I "think" the upper seat frames are different only because of the release mechanism.

Either of these seats will fit fine, but build date determines the style in 71.

Hope this makes sense? I can't explain very well in type doh.......