magnum head porting / pushrod pinch area / etc

Here is the tool I made & use to check amount of metal left in the pushrod pinch. I cut it out of 3/8" plate & the rod is 5/16" so there is .030" material left on each side. When a straight edge is flush with my plate there is .030".
I guess I need to get the cobwebs out of my heads.

Plate.jpg

pushrod pinch.jpg