[jsb5717]

Disappointing, yes, but doesn't look like the end of the world. In my mind I'd need to know why it broke. Did it break because it rusted or rust after it broke? What's directly above the break? Maybe the weight of what it's carrying is a little too much for it.

I think I'd be tempted to see if I could loosen the nut, and the others near it, and use a stout bottle jack to see how much lift I could get to see if I could separate the body a little from the support. I might try to slip a piece of 1/8" steel above that brace. If I could also slip a thin piece of plywood (1/8" would work) then that would shield enough to be able to spot weld the new steel to the old brace...especially at the break. Then pull out the plywood and reseat the nuts.

The plywood above the brace would also allow you to weld a 1/4" piece of steel along side of the existing brace, which sounds like what you are thinking.

Anyway, just thinking out loud with you. There are likely other solutions but I like the idea of reinforcing the existing if possible.