I have done this swap on both my 71 Road Runner and 72 Charger. All you need since you have discs already is the Dr Diff spacers, B-Body 11.75 pin adapters and rotors. As said above C-Body will not work. Your calipers, hoses and hardware are a direct swap. I used Wagner BD60475 rotors and Bendix CQ ceramic pads on both.

IMG_0400 (Medium).JPG