Actually that jogs my memory. The machine shop squared the block and I asked about the mains and he said they were real good and he had just touched them with a hone. he also said it took .003/4 to clean the deck; so I figured he should take .015 more instead of .020. Moral is : I should have had him check it since he had all the pieces by then. To the OP; figure in the small stuff on those heads. 1. screw in studs 2. guides or guide liners 3. best valves you can afford 4. springs and good seals 5. if the valve seats are very deep you can install new seats that will reduce chamber volume a little. Also you can do some gasket matching on your manifold and heads and maybe some bowl work. Do some reading and some of this stuff just takes patience and time.