Tomget, we will hope your measurement was wrong. If you end up taking the heads off, it is a lot easier to do the measurement. You can then do each end, or all four tabs located on the side. Almost never are all four the exact thickness. Not sure which method is best: average all four, average the ends, or just go with either front or rear measurement. Maybe someone else has a suggestion there.

I had my intake flange milled .046 in. due to head and deck material removal.
That completely removed the upper part of the flange, and actually just began machining away the rocker cover gasket rail.

The motor had a net loss of .042 in.(.035 off 113s and .028 off deck), so the "Books" called for .058 flange mill. Guys on y's forever said to just take off the same as the net loss, .042. So I just went a little higher. Good thing. It looks to me like much more than .050 off of flange is a no go.

 

Thanks 46Yblock