what i would do is buy a [ hel-coil] kit, they give you all u need in the kit,drill the hole out with the drill they give u,then tap it then insert the hel-coil and u eill never strip out or cross thread again,put some never cease on the bolts so they dont freez up on u again,check what size bolt then mach with kit.i use them a lot,when building motors i replace all the taped out hole in the heads with them, they are the best there is a penitration oil called [koil ]and that **** will unfreez any thing,i used it in the navy.spray it on let soak for 2-3 hours and bammmmmm it's loose,

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