I don't know how the vice-grips thing is going to work for that bolt - I tried shoving a screwdriver into one of the three holes in the HB as well as a vicegrips and then a breaker bar to break things free and it wasn't going to happen. I saw a youtube video of someone who had made a special tool for holding the HB in place while he pried, but I would rather not make a custom tool for a job I may only do once or twice. Not sure how the no-tools method worked out for others - maybe if I had a 2nd guy on the vicegrips I could make it work...
So I decided to buy an air compressor and an IR last night - got home too late to try them out, but that's the new plan.