I have an '85 CJ7 with an AMC-20 Rear.  From what I am gathering this rear is not a very durable rear.  I have a 4" Superlift kit to install and will be running 33's.  I am not looking to get into hard-core crawling, but I would like to be able to give the jeep a "beatint" and still be able to drive it off the trail.  

I would really appreciate it if someone more knowledgeable than I would take the time to give me some advice.  I need help!  

For your intended use I'd say slap in a good set of one-piece axles (Superior Axle And Gear makes a good kit) and run it.  

Great.  I will look into that.  Thank you.  

I have an 81 CJ with 33s on it. The one piece axles are great to have. My only problem was it couldn't handle the power of the 360 and the tires. It kept grinding the bearings into the brake backing plate. Did it 3 times and then decided on a Ford 9". Found one in Minnesota for $300 plus shipping. It was out of an older Bronco. It would bolt straight up if it had the spring over conversion but I haven't done that so I had to weld new sping perches on top of the axle tubes. After that, no problem what so ever.  

My AMC 20 has lockers , 4:10 and full floating axles. I run 33s and do not baby them. The rear end and axles hold up very well, however the AMC 20 tubes can bend and/or rotate with relation to the diff. If I were doing it over, I would look for a 44.  

for relatively light use the AMC 20 isnt horrible, but one piece is the way to go. If your worried about it holding up a 9 inch is a solid piece. maybe look into a Dana 30 or a GM 12 bolt,   these axles are pretty common place, check out your local junk yard and see what you find.  

I still have a lot to learn about four-wheeling.  By 9 inch, you mean Ford 9 inch, correct?  And what exact years and models will fit.  I do not really want to spring over my Jeep if I can help it.  There is a place not far from where I live in PA that sells Dana 44's, among many other parts, that are from Wagoneers.  They claim they will bolt right up.  

If I am thinking right, it was out of a 66. I can't remember because it was about 8 years ago. Like I had said, it will be a direct bolt in if you have a spring over on the Jeep. Otherwise you will have to weld new spring perches on it. Even the bolt pattern on the wheels matched up. The only thing was the Ford 9" was about 3 or 4 inches wider. You can see it once it is on, but it actually doesn't look bad at all. If it ever bothers you, you can replace your front end for a wider one or get off-set wheels. Some may agree, others won't but in my opinion, while you got everything out, go ahead and replace the yoke on the axle, rear end oil, and if possible bearings and seals. It is a cheap preventative maintenaince issue that can save you a lot of headache in the future.  

messure up where everything on the rear axles is located. spring perches, shock mounts and brake lines stuff like that. even wheel studs patterns. and look for a dana 44 out of a newer jeep that like you said the yard near you sells them. just make sure you get the same gear ratio that you have now in your jeep. that way it can be a direct bolt in.

ford 9" axle are nice if you can find them. usaully around 1966-70 but they are getting harder to find. but sometimes you can get a good deal. I bought my dana 44 front axle for $150.00 and it was out of a 1967 bronco.  

Is there a quick and easy method to find out my gear ratio?  Is it stamped on the rear?  I figure with the addition of the AMC 360, I won't need to gear it down with a lower geared Dana 44.  

the numbers are stamped on the ring gear, so if you pull the cover and rotate it around untill you find it, or.....you can count the revolutions the pinion (drive shaft) makes in one full revolution of the tire(axle). with an open diff only one of the tires can be allowed  to turn, 3 3/4 turns is 3:73 and 4 turns is 4:10 ect.
I never saw the last post till just now, hope you got it figured out. AMC axles also have a letter code you can look up in a table. The code is stamped on the housing boss to the left of the diff cover right near the axle tube.  

you can now buy the dana 44's out of a new rubi with the lockers and everything already installed... might be something to look into... but it might be a bit more pricy then you're looking for too...