my original idea was just mounting a vertical leadscrew with a handwheel on the side of the head, to push the quill down. it would have been annoying to use, but very simple to build. but i realized that will probably interfere with the belt case on top, making it much more of a pain in the ass.
i think i gotta go fancier and fit a worm gear to my quill handle somehow. need to mull it over a bit more, still.