I've put a Speedway GM caliper/disc/emergency brake combo on my 9" rear and found this nugget of info to getting a good pedal and handbrake.
Never heard of 'gravity' bleeding brakes before!?
I ignored the instructions and just bled them normally.
One caliper is perfect but the other must be sticking/got air as it seems to be pulling piston back in a smidge after pedal is released !?
So I'm off out to follow their instructions