I did the "tie a thread to a bolt and work it inside the frame so it is sticking out" method. I used smaller bolts (I think 3/8 x 1.5" vs. the original 10mm) so they would slip past the existing threads in the hole and although they should be tack-welded to the frame to hold them in place, I was able to thread and tighten the nuts on the brackets without doing it. For the back hole on the driver's side I used 2 threads on the bolt, one at either end, so I could use tension on the back side to get the tip to wiggle into the hole. Took a couple tries to get it right on the driver's side, but not a huge deal at all. Happy to know that my sway bar brackets are on there but good.