Junkyard F body vs New A body?

What I have access to now is 76-89 FMJ stuff. I grabbed the last 2 sets of 78-79 B,C body large 11.80" rotors, caliper brackets and calipers for my 2 project cars. No more A body spindles. All of it gone. Couple more volare/aspens, and a few dippy/fifth aves I havent pulled em from yet. I don't have 72 and older rotors.