hey vic. it seems you had to spin the gear box to get it out. what a pain. also im referring to backlash as the rocking of the gearbox on stopping, which indicates the wearing out of the worm gear. the end play you refer to is the adjustment for the backlash common on otis geared machines. you are basically making the friction point of the worm gear and crown wheel closer/hard up against each other to stop the backlash motion.i mentioned that the crownwheel bearing that fit to the mount are shimmed to fit square not for up/down adjustment.it looks like there is no worm adjustment on this machine/s.
glad it worked out for you vic.
cheers mate.