A novel concept, measuring stuff before you "fix" it... I've seen more stuff made worse or ruined by extra machining. 14 years and still running strong? How could that be, without all that needed special machining? ;-) That would be a topic for another thread. The only engines I kept were virgins. Not interested in someone else's "rebuilt" engine.
Once you mill a cast iron head, I have never seen them need to be milled again.
