Larry you're right The El Cheapo doesn't have a pressure gauge.
Instead I use my digital tire gauge, that's why it is El Cheapo.
It's amazing how many approaches there are for doing a job that has to be one of the easiest there is to do.
I don't see the logic in destroying the resevoir, just empty and swab.
When I pressure bleed I pump the pedal so easily, this dislodges any sediment in the piston bore.
Oh well. to each his own; I've been doing it on my 300E for twelve years and have yet to service a caliper or the master cylinder.
Happy Trails Beep Beep from Houston!!!
Donald, El Cheapo
You may be surprised at what is there for pressure bleeding your brakes