I've never bled any master cylinder and have never had any issues. I sometimes like to leave the lines to the master cylinder loose and pour the the fluid in, and wait for the lines to start leaking, then tighten them up. But if I've painted the master cylinder, I won't bleed it. Just hook everything up as its supposed to be, fill it with fluid, pump the pedal and watch the bubbles come up from the resivoir, and once no more bubbles, then just bleed it normally. I've never had any issues doing it this way, on any vehicle: 90 ford 460 class a, 85 Pace arrow chevy 454 hydroboost, 79 chevy truck 454 non hydrobost, 95 gm hydroboost, and various other makes and models (VW, porsche, honda, toyota, etc.).
