The ring gear on an AMC 20 axle is actually a little bigger than the ring gear on a Dana 44 axle. The tubes are a little thinn3er on an AMC 20, but you can buy a cheap truss for that. For the axle shafts, you can even get the Warn full floater kit, which really beefs the hell out of it.

I've had mine rock crawling in KY with 35" BFG MTs, 4.56 gears, and Lock-Right. I'm more worried about my Dana 30 front axle, so I carry spare axle shafts for it.

1977 CJ-7, fiberglass body, AMC 360 w/ headers, DUI ignition, Edelbrock intake and Holley 4150 carb, TF999, Dana 300, 4.56 gears lockers, York air comp, 4" susp lift, 2" body lift, BFG 35" M-T tires, Megashifter, AGR pump & box, REP8000 winch.