Originally Posted by jjzx2sr
The best method may still be to apply heat to the bolt and hope it expands it slightly.
Nope, like sailor wrote, exactly the opposite. You apply the heat to the crank which is why it's not an easy thing to do in this case. You'd have to drop the oil pan, and at that point you might as well see if there's some way to shove a block of wood (not metal) between the crank and the block when you've gone that far. You'd be more likely to start a fire trying to do this with a propane torch which is what I've always used for heat. Now you can use heat on the bolt to disintegrate the thread lock if there is thread lock on there. You might be able to get away with heating the bolt until the crank got hot, then cooling the bolt with dry ice, but I'm afraid you'd seriously damage the integrity of the pulley at some point in there since it's the weakest metal link.
Where's the OP? Has he already broken this loose- or broken the head of the bolt off?