I wanted the small bumpers for my wife's '73. I just relized that it has the small bumpers. It just has the bumper guards on them. All I have to do is take them off. Doh!
Well, sort of. The back bumper is the same but it sticks out further than the 70-72. You can just get the early brackets and bring it in but you will have to remove the lower filler panels and fill in the holes. The front is bigger than the 70-72 but smaller than the 74-77 It would require all the bracketry plus a bumper to convert.