Thanks for the encouragement, guys! I've been using a VCR as input and I thought I'd get something on channel 3 or 4, but 4 goes black the moment I turn on the VCR. I was getting something to happen on channel 6, so I went with that...?
I had Rio Bravo playing on the VCR and finally got this:
Wow, John Wayne and Dean Martin are actually recognizable through that mess! I couldn't get the picture to stop overlapping from top to bottom. I did finally get the horizontal to lock and the vertical to more or less stay in place. Horizontally it would jiggle just slightly here and there, and vertically it would roll here and there and sometimes it would go dark and flip out and I'd have to readjust a few things again. I can't get it too bright without being washed out.
By the way, here's what that audio output transformer looks like:
I took this picture while I was recapping. You can see the burn mark pretty clearly. The schematic has readings for this transformer but they're printed really small. I think it says .5 Ohms on the "out" side and either 380 or 580 Ohms on the other side. I did check for the .5 Ohms and I got more like .004 or something, shorted I guess. I'll have to take a closer look at it next time I pull out the chassis. I wonder why it crackled for a bit and gave up. Arching inside the windings? It did this the first time I ever turned on this tv, but to a much lesser degree. This time it actually sputtered quite a bit before it gave up. Hasn't made a sound since.