I have been cutting some metric threads recently by swapping 33 and 34 teeth input gears but today I finally caved in struggling to undo and tighten the quadrant pinch bolt without removing the bull gear and drilled a 9mm hole in the casing for access the bolt with an Allen key on end, and when not in use put a car wheel cylinder bung in the hole.
Sacrilege perhaps but it works for me.

