Just a quick update...
Here's the new master cylinder in place:
Originally it had a GM single pot master (with a screw top- believe they were only made in '63) but when I ran the casting number on it, it came back as a single or a dual. Figured to be on the safe side I might as well go with a dual. I forget what material the brake lines are made out of, but they have sort of a copper tone to them- sort of reminds me how most of the brake and fuel lines used to be copper on these old cars! Had a kit for 1/4" line and was able to use correct fittings to go right into the master cylinder without crude looking adapters- definitely helped with the space restrictions there too...
Also drilled and pop-riveted the driver's side door "flap" (no more green tape holding it down!):
And for the heck of it I went and installed my mirror:
