why does dial indicator say .068" ? I would throw a rod and piston from one side in to the other side, just in case you have the short ones all on 1 side (probably the block is the reason 1 side averages .010" different) Then just cut 1 head .010" to even out the compression ratio. what is the piston part number-look up valve notch cc. how much compression ratio you can run depends on many factors! closed chamber heads? run a thin gasket to get some quench