On my 28 sedan I'm using 9 inch front rotors with metric calipers and on the rear a set of 11 3/4 rotors and GM calipers like they put on the 76 chevelle. I am going to use a corvette style MC, I have a alum one, brand new with a 1 inch bore and 1 barely used with a 1 1/8 bore. I'm putting a adjustable proportioning valve in the rear. I'm thinking the 1 inch should work ok, anyone have opinions?