2007 GC2310 that goes a little high on the tachometer. I want to adjust the throttle stop in a little to keep it a little lower (for when the wife or FIL are running it) so that it can't run right up into the red zone. Problem is I don't know how to get the cover off of the adjusting screw. I'm pretty close to cutting it off with the grinder. Anyone here who can point me in the right direction?