Flanging and brazing or using silver-bearing solder is a good choice in many cases. There may be some odd curves and angles for you to deal with, but you can work around them and they will be the same no matter which direction you go. The best thing about brazing and especially silver-bearing solder is that they work at much lower temperatures, so you avoid warping and burn-through. You can use a MAPP torch with silver-bearing solder, in fact and it definitely will join ferrous metals if you use the Harris acid flux. If you make a mistake or need to re-position, doing so is not difficult.
One other possibility if you're flanging is J-B Weld. Advantages: no heat, flexible assembly time and plenty strong. Plus it is cheap. Over 40 years ago the roof pan separated from the upright pillar on my truck (very common problem in AD trucks) and I repaired it with J-B Weld. All this time later it hasn't gone anywhere.
~ Jon 1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
