If the cylinders weren't finish honed for moly rings, then you can experience problems by installing them now. I think Egge used to rebuild rocker shaft setups and replace rocker arm bushings. You will have to recondition the rods if you intend on replacing the rod bolts. Installing main studs typically requires the block to be align honed, but since you can't align hone a GMC block, you need to check and make sure it doesn't eggshape or close up the housing bores too much or it will have to be line bored.
