I don't know if you have a lock for the positions but when there is a lot of slop in a worn gear, I always keep pressure against it in one direction.... and lock it. if I have to back down, I back past where I need it and then turn back in that direction to   remove the backlash. I do that in my mill all the time.

Cheers, Jim ........................ Variety is the spice of life...............Learn something new every day