exhaust manifold leak

i have in the past on other manifold jobs, when the bolts are really questionable, is to just take the cutting torch and blow the heads off, remove the manifold, then i can get into heat the stud that's left, and they remove easy, a lot easier than trying to get a broken bolt out of the head. had a dodge diesel years ago, i spent hours getting the first side off, what was 14mm heads, where now 12mm, between the spray and was a real pain, the second side i figured i would try something different, and just blew all the heads off, took less than and hour and the manifold was off and all the old bolts came out with heat and vise grips...