My attempt WRT my TJ build was to remove the cylinder head and sand it down. I started off with loosening the 5 cylinder head bolts and they all loosened easily. Then i started in on the double ended studs and wellll...... They are on good. Since i didn't have a 12sided 13mm deep socket handy i had to use a wrench end and i just couldn't get the leverage to break them..... So i just decided to tape down the areas i didn't want to affect and did a quick grind job right on the block.
So...
So...