Milling the intake is unnessesary when you can just mill the intake side of the head of angle mill the deck of the head. When you mill heads it is usually because it was a little warped or you want more compression. Why would you not make the head still work with any stock intake? FE intakes are too expensive to go cutting into. You can take a straight .020 off the bottom of the head or the top of the deck before you need to worry about removing any more material.