Mopar brakes compatibility question

Ok...so my 71 demon has 9 in drums in the front. But when I bought the car, the guy also gave me some disk brakes(upper A-arms, spindles, rotors, and calipers) that have a 5x4.5 bolt pattern from an unknown car(but to me it would seem the upper a-arms are the same). I'm looking to put some big disk brakes on this thing, but I'm having a hard time figuring out all what is compatible. Obviously the ones that say there for OEM 9in drum spindles I know would fit without changing(for example, wilwood makes a kit for 9in drum spindles), but dont tell you if it keeps the same 5x4 bolt pattern or if it changes it to the 5x4.5). And how would I be able to put some of the other brakes(like the huge ones made for B and E bodies) on this thing? Heres a picture of the brakes in question. Sorry the pictures suck.