If the panhard bar is the right length and just needs a twist to get the ends to line up correctly, I would just heat the bar and give it a tweak, rather than cut it two and weld it back together. You can do that multiple times to get it correct and have a stronger bar than if you cut and weld.
I did locate a '70 truck with a Dana axle in it, and it has the correct frame mount, but there is no easy way to extract it from the truck in the junkyard. So I decided to resort to modifying the bar instead.
In most junkyards I've frequented, they'll roll a truck on it's side so you can get stuff off the bottom. If the frame is already toast, a cutting torch would make short work of extracting the frame mount.
