Can't get power brakes to work

I don't know what the FSM says, but I just screw the adjustable tip outward, then offer the MC to the booster until I feel the rod touch the piston and note the gap. I screw the rod in a little less than that and repeat until I can feel it touch with just ~1/16" gap. That gives slight piston displacement as you bolt it up (so tight and no lost motion), but not enough that the piston will not still expose the refill port when the pedal is up.