I searched, I read the "vacuum bleed", "reverse bleed", "gravity bleed", "pump 50 times".
Well I tried a bottle & hose on the nipple to apply vacuum. Got some bubbles, repeated about 20 times. Obviously wasn't getting anywhere.
So I busted out the pressure bleeder. The sun was going down to I dragged out the drop light. Climbed into the attic to get the mityvac, pressurized the master res to 15psi, opened the bleeder, watched the bubbles rise in the inverted bottle, pump the pedal 50 times with 5psi on the res, repeat about 20 times. STILL NOTHING!
I guess I'll try pressurizing the res, opening the valve, pressing the pedal & holding it down, closing the valve, then lifting the pedal with the pressure still on the res.