If you're planning on rebuilding the whole drum assembly anyway, check to see what size wheel cylinders are in there now. I've been using (I think... slept MANY times since the change) 13/16" wheel cylinders from an early-70's Dodge truck (I think also on early 70's Darts, too), and my 10x2.5" rear drums don't lock at all. Hard "panic" stops will still lock the fronts first, and I've never had a proportioning valve in the car. I'll be checking on 7/8" cylinders some time later this year, to see if it helps stopping some more, or starts to lock up again. I *THINK* the OEM wheel cylinders were 15/16".
Front brakes are 11.75" Cordoba rotors with (previously) 73+ A-body slider calipers, and now 2000 Viper calipers. Both appear to work about the same for the kind of driving I do. Daty's TSM rear disks are pretty nice, though, and I think he's pretty happy with how that part of his Hemification project turned out.
