Which master cylinder for 4 wheel disk brakes

... Using an adapter plate has one disadvantage: It move the MC forward and the brake pedal will be closer to the floor, typically by more than an inch. ...
Not for me. I used a newer MC w/ adapter plate on my 1964 Valiant, and the pedal is in the same place (photo, your results may vary). The MC is 7/8"D bore, which is the smallest I have seen (i.e. easier pedal). MC is for a 95-99 Mopar "cloud car" w/ ABS (Breeze, Cirrus, Stratus), and probably many others would work. I super-glued the 65 boot to the new MC (2nd photo). The bracket is from an Intrepid, on which I mounted an adj. proportioning valve. Haven't driven the car like this yet.