1971 bucket seats ???

Thanks, I never noticed over the years. It was while I was cleaning two up that I saw one with a chrome button. and then when I went to change the backs I notice the rivet difference on the black button style. 71 is a strange year, Many mid year changes to things that make the parts hard to find on all A-body and B-body cars. I have three 71 B-bodies. Two Roadrunners and a Satellite and all ready found a different count of headliner bows.