I decided to finally stop putting off looking at the tank.....what a wreck! The PO left gobs of MIG welds on it, something that looks like some type of sealer that was cracking and lots of rust on the inside. I took the petcock off and it too was a mess, so off to eBay to find another tank. One seller had two tanks, a 1982 185S, which is what I need and a 1983/1984 200S tank. The 185S tank was a bit beat up, but the 200S tank was in immaculate shape, no dings but it is painted white....no biggie, since I'm going to sand it and paint it with the Krylon Fusion Red Pepper, so that everything matches color-wise with the plastic and forks.
Here's a pic of the new tank. I'll take a pic of the old tank later, so you can see how FUBAR it is.