So I figure why not do a bolt mod and switch out all of the electrical insides with new ones from a PC/5250.
I probably should have waited for a new terminal keyboard to try out Soarer's Teensy. I ordered the parts before being advised on Geekhack that it would be cheaper and easier than what I am doing.
Now the parts are here, and I need some help. First, the PCB controller has two four pin connections. Only one can be for my USB cable. One is J17. The other is J21. I assume that J17 is the correct plugin since more circuit traces run straight to the big chip in the center of the board. This is a layman's logic. Please correct me if I am wrong.
It also appears that the new interface between the membranes and the controller board occurs when the PCB is bolted to the keyboard shell
and the membrane tab is bolted in place beneath it. If someone can confirm this with a pic, that would be awesome, so I can fabricate a new interface. If you don't have a pic, you can tell me if this assumption is right or wrong with a short description. The old innards are much nicer. I can see why people stick to the old hardware and build converters.