Real quick, which way/ how much do I need to turn the screw in the vacuum modulator to incres my shift point?

You need to turn it clockwise if it is the big black one, the screw maybe spot welded use vice grips to break it loose then seal it with RV sealer,if it is the small one the screw is in the nipple use a small screw driver.But check both for fluid gas or water first.This adj. won't change the shift much.A governor change will change them a whole bunch.But give it a try...FRED