I need to install brake lines, MC, and prop. valve. Help!

Many people use a manual MC with disc brakes (search posts), it depends on how strong your leg is. Seems most prefer a 15/16"D MC. A smaller bore (7/8"D) will give less effort, for more pedal travel. You sure don't want the pedal bottoming out on the floor, but usually not a problem if you get all the air bubbles out. Look on rockauto for specs. I recall seeing a Volare MC with 1"D for manual disk brakes, but their pedal might have been different. Are you sure your body lines can't be re-used? In my CA cars, what looks like rust is usually more like baked dirt and they cleaned to shiny real easy. I think all brake lines are 3/16"D, even newer "bubble flare" ones spec'ed in mm. The only difference I have seen is the 1/4" tube from the single pot MC in Mopars before ~1967.