Hydraulic Clutch Master Cyl diameter

I called Wilwood and they told me what bore to use with a McLeod hydraulic throw out bearing.
I've got a friend who used a stock fork and speced out a slave cylinder which he made brackets for on his bell. A little too busy for me. My set up works great. The bearing was the expensive part like 450 but the master was only like 80 and I have a 3 finger PP. A diaphragm PP would be very soft like a new car.