[mrmikey]

Clean, clean, clean is my advise. I've repaired similar before but imho it's a crap shoot at least in my case. You don't want to aim your heat on the tank as the tubes are soldered in and you'll end up melting it out somewhere else.
Small wire and a small tungsten is a must as well, I used .035 from a spool, I tried both 4043 and 5356 and had better luck with the 5356. Here's hoping someone else will chime in with some more advice....Mike