[ronaldk]

Maybe this will help. My son bought at sears a set of bolt remover tools that have hardend like teeth to grab a worn stripped bolt head. I know you have a broken bolt but maybe one of the smaller removers like for 8mm for example use gauge if you have on bolt for size or go to store with bolt in hand for fit. may just fit the bolt itself. Its a tough spot to be in I know you need it to move and not break again with alum head. I would spray also since you now have access. Most would heat head I would try to heat only bolt so it expands possibly breaking its bond with head maybe take old exhaust gasket and slide over bolt trying to keep heat only on bolt. once hot spray with (I LIKE liquid wrench penetrating oil yellow can)to cool then try that wrench from sears if it doesnt move repeat until it does now you need patients. hope this helps I know how you feel been there Good luck