As previously stated Dave, they aren't necessary and I'll do the job properly so the head doesn't have to come off again. If decent bolts were good enough for ford the get over 300kw out of a Barra and last 700,000km in a taxi then revised well made bolts are good enough for my ute. What kind of company that has 2 subsidiaries, one that can make bolts and one that attempts to? No thanks, I'll stick with blackxt suggestion for mace engineering, the more people I ask the better they sound.