Hmm. This gets more and more interesting the deeper I get.
So the PlayStation I ended up getting and modchipping works well enough -- I have to replace the laser mech, right now all it will boot into is my burnt copy of the 240p test suite -- and I have to figure out a better solution for burning stuff at slow speeds so it can more easily read the disks. Apparently the PS1 is very notorious for having finicky-at-best CD drives.
The Trinitron is a complex beast. Provided I can find the jungle chip, I should in theory be able to tie 75 ohm resistors to each of the signal lines for the OSD to get ports for RGB on the back, which is a nice little project -- I'm not comfortable enough with a dremel to even start with trying to panel-mount a real-deal SCART connector, but I'm comfortable enough soldering now that I could put together a little breakout cable for SCART to get phono plugs for each of the signal lines and stereo sound, and I have a set of those stepping drill bits so it wouldn't be a big deal to make holes for phono plugs. I'd be happy enough with S-Video if I could get the geometry dialed in right. I can *almost* get it perfect but the image is ever-so-slightly rotated, and the service menu lacks a PROT option so I'm guessing I'll have to manually get in the cabinet and mess with the yoke to fix that. Even more frustrating, despite my writing my new settings, it just refuses to actually save the settings I set in the service menu -- I almost wonder if it's got a battery that powers some kind of SRAM chip that holds those values, and the battery has long since died or something.