Bench Bleed Master Cyl Question

"That's it, I'm out". I was confident that the problem was "solved" by using an incorrect stop bolt, which I wasn't wild about doing anyhow, but even now the same issue re-appeared again. The master is pumping for the rear system, but with WAY less force than the front. Maybe normal, I don't know, but at one point I know it was pumping a lot more than it is now. I can see that the piston is moving, but only slightly. The investigation continues. I'm able to bleed the rear brakes, getting fluid from the wheel cylinders when bleeding, so I know it's pumping fluid, BUT I can still turn the rear wheels while my now angrier wife is again handling the brake pedal. Adjustment? I don't think so cuz there's normal drag on the wheels when turning them. So, I removed the brake drums and had her mash the pedal. If I remember correctly one time when I was a kid I forgot that the drums weren't on (not this car) and mashed the pedal, and it was dramatic, with shoes and springs and s**t flying everywhere. This time no such fun. All that's happening is only one of the shoes on each side is moving very slightly, but not nearly enough to provide braking.
I dunno, maybe the rebuild kit is not getting along with this master, maybe there's some issue with the re-sleeving. I found another correct master today that I ordered so I'll try that. This whole thing started 2 years ago and at that time there was not a correct master to be found anywhere, that's why I had the re-sleeve done, and if this wasn't enough, I stripped the threads on one of the coiled brake lines that go into the master. I wouldn't even have mentioned it except to give a shout-out to Nick at "FineLines". I bought all of the lines for this car from them. He didn't even have me in their system anymore since it was so long ago but still is sending me a replacement line for free. This kind of stuff is great to see in this hobby.
Again, thanks for everyone's help. I'll consider this thread closed with no definitive answer, but I'll report back after I install the next master.