Here’s what the answer should have been: Don’t use a torch.
cut out with an angle grinder/recip saw. I should have known this, same as rear outback bolts, pointless to try to save them around here. My Tribeca has little rust so I was thinking it might be different...nope.
I torched the €+<%,*! out of it, Oxy-propane torch, burnt all the bushing rubber out and then got the bolt red hot on both ends, liberal amounts of yield, and torched the sleeve, and quick cooled it a couple times...to put out the flames on the burning undercover and the HVAC metal heat shield I had in place which lit up and melted too
then I used an old socket bolted to a long piece of all thread so I could wail on the bolt from behind the car with a huge few pound steel mallet swinging as hard as I could.
no movement at all. The bolt is seized inside the inner bushing sleeve.
so I’m guessing its best to cut these off and replace the bolts each time. That would’ve been way easier. Now that the bushing material is melted away and the Outer sleeve moves more, theres more room for making an ideal cut.