The intake valve/piston clearance is pretty close unless the valves are recessed the same depth as the milling cut, further compromising breathing. Flycutting the piston might be a possibility if someone just has to see lots of PSI on the compression gauge for some unfathomable reason. It's really not necessary on a stovebolt, and will probably cause destructive detonation due to the shape of the combustion chamber.
Let me respectfully suggest that you actually look at a stovebolt cylinder head sometime before continuing to propose unnecessary modifications.
Jerry
