Not to belabor my snarky reaction to being treated like a lazy newb, but my problem wasn't an inability to use search tools (I only use phpBB's search on non-public / invisible-to-google boards), but a lack of search terms before researching.
Perhaps I should've asked if anyone had some suggestions for search keywords relating to interfacing other-than-Classic logic boards with the Classic's video system.
Regardless, I found the threads I was looking for the brute force way, and learned a lot about a lot of other topics too. It's not a chore to read the helpful info stashed away in unrelated threads. I'll probably read the rest anyway. Beware of zombie threads if, heaven forbid, I have something to say or ask about.
marky: Thank you for the actually helpful search advice though!