What's the backlash, measured with a dial indicator on the ring gear teeth? The only way to correct that slack, and not create a deafening gear whine, is to install new gears- - - - -which nobody is making any more.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!