Well, I know for a fact that all 70 models have holes in the front and rear for a clip with a screw. I have a 70 Challenger and 4 or 5 70 Barracudas at the shop. This is a late 71 Challenger and it was a pretty rust free car. The back has all the studs intact. It has the two holes at the bottom for the metal spacer to keep the window from sliding down after installation. It also has two holes that appear to be factory in the middle of the left and right side. I guess they used a couple of screwed clips there. I did look at a friends 71 Challenger yesterday and it had some studs where mine where missing and some screwed clips in places mine had studs. I sure body shops over the years did not worry about replacing the studs and just screwed clips in place where the studs were rusted off. Of coarse my car has had a little welding and rust repair before I got it in a primed condition. I did find a paint supply store that said they could order me the studs I want that pop rivet into place instead of welding them in place with a stud gun. It has been years since I have seen any of those.