One suggestion... its rolling so take it to a good alignment shop and get it checked/aligned "as is". That would give you a baseline.

With offset bushings or aftermarket UCA's or spacers on the LBJ mounts for negative camber, the factory mount locations work fine for a handling application. If it is close now, good to go in terms of basic location.

If the current bushings are more or less intact the alignment check should be meaningful. If they are completely beat up, squished ect. may need to do at least a partial rebuild first... but you have to do that soon anyway so no biggie.

As far as welding, I am in the "I can melt metal and get it to stick together camp". For something like that I would (and did) take it to a shop that has successfully done that type of repair before.