What Disc Brakes to Use

When you put on larger drums, did you change the backing plates & shoes, too.
I put a full 75 Valiant front end (K-frame, too.) under my 72 Demon which gave me manual LBP disks & a factory engineered sway bar that don't interfere with each other. I'm happy with it.
I may get razzed for this, but you may want to consider a softer brake pad for the front (organic vs. carbon). The carbon metallic brake pads are harder and work better with a little heat in them. I don't see that as an issue for you since you're adding mileage ¼ at a time.