While you are at it, why don't you consider milling the
head a small amount as well? It will increase the
compression ratio somewhat, give a little boost in
power, and increase gas mileage noticeably.
How much? you ask. Try maybe .040 thousands. Then
tell your machinest that when he seats the intake valves,
be sure that the face of the intake valves are even
or below the new surface of the head. And yes, you
will still be able to use 87octane gas. you go man...