440 Help Needed

Throttle blades are cheap. Are you suggesting he doesn’t now how to close the throttle? Or maybe he has the throttle cable adjusted wrong?
So that's what you gleamed from my post.?
Guess I need to say it again.
I wouldn't be drilling any holes in the carb plates until I was 100% sure that nothing else was causing the need to open them that wide..
Example:
ignition issues, mechanical issues, vac leaks etc..
Drilling the plates, just to find you then need to replace them after the real culprit is found, is not the smartest thing to do... no matter how "cheap" they are..
Pretty obvious steps to follow, if your a trained licensed mechanic..