XJ Rear Leaf Spring Swap Problems

So, the leaf springs on my XJ were sagging and I thought I would save a few buck and swap them out myself. The problem is that the bolts in the front froze up in the bushing sleeve and I'm pretty sure that on one side the weld-nut in the frame busted loose. I assume I could "hot wrench" the spring eye to be able to get to the bushings and get them off so I can remove the bolt. What in the world do I do for the busted weld nut? I really don't want to take the spring perch off and have to reweld it. is there an easier way?

Cut a hole in the subframe rail right below the nut to gain access. Heat the nut up a bit and then slip a wrench in to hold it.