I got an exhaust and I was putting it on my car (2013 wrx) and had to disconnect the exhaust after the midpipe. The bolts were rusted so I PB blasted them, and then got one set of bolts off. When I went to the next set I stripped the head of one of the bolts with my wrench and now it can't grip the bolt at all.
What is the best way to get this bolt out that does't involve heating or any sparks like a grinder due to the close proximity to the gas lines?
I was thinking a nut splitter and if that doesn't work make a flat head screwdriver groove in the bolts with a hacksaw.