Marty,
The aspirin trick is here, beginning with post #26 ..
http://videokarma.org/showthread.php?t=257295&page=2
If you're dealing with a tiny stub of wire sticking out of the flyback tire, it'd take a bit of improvisation to get the stub immersed in the hot acid. Or maybe you could swab it on with a toothpick while still hot.
The arcing and simultaneous blue flashing in the 6BG6 are probably related. The overload imposed by the arcing could have caused the blue flashing, and the tube
may still be OK. No guarantees though.