well with any build were i mill the deck i shoot for o or 010 so the piston is O or in the hole 010 i try allways for a 038 head gasket most all the time . as for the 10 vs 12 .there are things you can do to beef up the 10 bolts .how long will it hold up with no work is hard to say places like DTS a Randys and other may help with parts your rear end may need or up grade . most all the car/truck rear ends stuff is all i ever played with street/hot rod and all out drag and them were ford 9s