I have some seriously seized bolts that are keeping my from pulling my manifold exhaust (cracked). I have shot them with pb blaster, and am using the largest breaker bar that will fit. But can get them to budge. Due to their location set into a little flange I can not saw them off. So I'm stumped.

Does any one have a MAP gas torch or something similar I can use to heat the nuts up in an attempt to break them loose?

Any help or insight is greatly appreciated.