1973 Duster 9 inch brake upgrade questions

That's the info I was looking for , thanks! I was scratching my head on that. I have two cars here, a 1971 Demon and a 1973 ( 8-72) duster,Dmon has 10 inch front 10 inch rear. Duster has 9 inch front and 10 rear. The upper ball joint looks significantly larger on the taper part of the shaft and the nut is much larger than the 71 as well. In any event I'll give screbird a call and see wht they think, that would work. Thanks!