Hi everyone

I needed to replace the exhaust manifold gasket because it just started leaking. I bought the gasket kit for the manifolds, cat, and crossover pipe . Also a new 02 sensor. I was almost successful in removing all the exhaust manifolds studs but one broke on the drivers side. It was the lower one closer to the head gasket. It still has about 1/2” of it showing. So I guess I’m lucky it didn’t break off flush. Can I use a MAP gas torch to heat the stud and try and remove with vise grips? I don’t want to overheat the aluminum head and warp the head gasket. I wanted to try heat first because I have the map gas and a regular torch. If that doesn’t work I’ll get a welder and try and weld on a bolt to the remaining stud and try and unscrew that way. I just needed thoughts on the map or torch heat with aluminum head....
Thanks in advance!