Did it have a bright raster before it went Ppphhhht!
I hear peaking coils can give problems on those sets. Some folks have been saying the Mica caps in the 621's & 630's are having problems too after 60 years.
I haven't had the pleasure of working on a 630 yet so I don't have any specific ideas.
Hopefully you'll be able to see what let go, maybe a cap hooked to the wrong place. Seems like I always get at least one wrong on every set!
BTW, I have a junk chassis if you find you need a part.