Do you happen to have an image of your homemade pressure bleeder? I may get inspired over the weekend and build one for fun.
This is from 2002, probably not long after I made it.
I started with a garden sprayer, take the handle and black hose off, swap it over to clear hose so you can see if any air is getting pushed up to the reservoir. Drill a small hole and screw in the pressure gauge. I also added another fitting with a compression type connection, to the ball valve (red handle). What I will sometimes do is turn the air down on my compressor to about 40 psi, then you can see another regulator, it is for an air brush setup, I turn this down to about 15 psi. Makes it so you don't have to keep pumping it back up. Do not go about 15 psi, you risk blowing up the plastic reservoir.
The adapter on top of the reservoir took a few tries to get it to work well. It's made out of some scrap 1/4" aluminum plate, the big eye bolts have a piece of chain that loop under the master cylinder. There is a piece of old inner tube under it (with a hole in the center) that makes it seal. It worked really well with those older reservoirs.
I was in Harbor Freight today and found a decent coupler for Tru Flate fittings, so I'm good for getting connected to the nicer adapter for the Cruiser master cylinder. I guess the other thing I have learned about using this with newer systems is to not allow air into the system, as it messes up the ABS regulator. So my plan with the Cruiser is to suck out as much of the old fluid as I can with a turkey baster, then fill back up with fresh fluid, then dump the rest of the quart into the jug. There's also a step recommended where you run the booster pump, you need TechStream to do this.
Pressure bleeding is really the only option for me, I don't have anybody here to pump the pedal.