I know what it's for. So you'd tell someone to mill .060 or more off a head and waster a casting rather than fix it right by d caking the block? That's just stupid. I say it over and over and over since 1980, if you are running a 340 and the heads are the open chamber type the piston MUST be out of the bore to get the compression up.
If your engine builder doesn't understand that, kick him to the curb.
