If the outside diameter of the backing plates is 11" it should be a for a 10" drum. If it's 5x4.5" that would be a 10x2.5" drum set up. The backing plates for 11" brakes have a 12" outside diameter.
I see. Alright, well that would explain why the 11" drums and many other parts didn't work. Will my brakes have to have the exact same set up as a roadrunner? On the AMC it has a more similar set up to a Ford with the springs and the self adjusting kit, and that's how it was when I first got it.
