The Eaton was pretty much the standard 3/4 ton and 1-ton rear end, and was used for several years. It had several ratio options, and was even available with a Detroit Locker differential in the later models. We ran them in dirt-track race cars in the 70's, behind 500-HP engines without any real problems. They were goshawful heavy in those dirt cars, though! One identifying feature is a backlash adjustmnet on the side of the carrier housing on the driver's side, that bears against the side of the ring gear when it's coasting. Tricky to adjust!
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!