Wow, to say that's yellowish would be a huge understatement!
But congrats on the free one, it's in very nice condition with all the manuals and stuff, plus you can't beat "free"
If I recall correctly there should be a couple of transistor that specifically manage the sweep circuit, one being the horizontal output transistor. They might be shot, unfortunately the dead mac scrolls only cover up to the SE/30, but you should be able to find some diagnostic help searching the threads in the compact mac forum!