69 Cuda bucket seats

66 seat frames are close enough to use. Their tracks are different and they have the full metal back like 67s. Those differences can be overcome.
The top of the back frame in a 66 seat is round tubular and wont accept a headrest. For 67 they formed that piece square which made it about a 1/2 inch shorter and punched 2 holes in it for the headrest posts.
I think those oval headrests are ugly. My 67 ragtop is sposed to have them but it wont. Did you know the proper name for them should have been neck protection addons ? Not sposed to be a pillow. Originally designed to help prevent whiplash.