Hi Racer X, A couple of suggestions If I may. Like Peter Jack said, grinding the welds down to smooth out is a good idea, but try not to grind on the parent metal of the tank. You said you were going to wire brush the welds to clean them up, I suggest you use a small stainless brush and if you are using that brake cleaner I see in the pics you posted, DON"T USE IT!!! Get some acetone, clean with ss wire brush and wipe weld area down a second or third time with a clean rag and acetone to remove any vestages of dirt or residue.You didn't say what size tip or brazing rod you were using, or what kind of flux you are using. The torch tip size and the correct rod size can be determined by a good welding supply shop,, the flux can get a little tricky, too much, not enough, but it maybe best in your case to use pre-coated brazing rod. The correct size flame is also a factor, again hard to describe here, but that good welding supply shop should have pictures which will help you to get the flame right. When starting to braze, I would turn the tank so the top was on the table side, so I could run my puddle into the seam of the thicker part of the tank. But I would be heating the metal from thicker side to to the thinner portion so I could have better control of the brazing material into the seam. Remember, you can maintain control of the heat by moving your torch away then back into the puddle, that way you won't be blowing holes or warping the parent material. Also, dip your brazing rod into the puddle take the rod out only so far so you'll have a preheated rod for the next dip. Don't melt the rod with the torch flame. have the puddle do it. So there you go, not much to brazing..... Yeah Right.. Oh 1 more thing when you are positioning the tank make sure you are comfortable, even to the extent of building supports for your arms so you can maintain a comfortable position at all times... Hope this helped, good luck Mike R.