Rear disc or not?

I am going disc on the front. Is it worth it to disc the rear too?  Right now hard braking slides my rear end around my passenger side almost instantly.

sounds like something is not working correctly  the rear is easier than the fronts , But you need to replace the rear axle bearings to a green bearing. I have the conversion posted under the a100 parts link.
http://centralcarolinamoparclub.com/jeep-to-8.75-rearend-conversion.html

Is it a good idea to change the rear tapered bearing in general? Or is this just if I go disc on the rear.

On a side note, I wonder if I can use a late 90's jeep grand Cherokee ABS system? Should be similar weight distribution.

simplicity =will NOT create headaches!!!!!!!!!!!!!!!!!!!!!!!! remember - the front brakes stop over 75% of the vehicle!! rears have never needed discs-wernt mass used till 80's up to creats sales & marketing over others using drums!! still today many mfg's use drums on rears!!

The last time i pulled the axles i installed the green bearings but have not done the rear conversion yet. but i know of 2 people who did the rears along with the fronts, and are happy with the swap. my guess is you can buy the parts at the junk yard cheaper than 2 rear drums, the stock roller bearings are stronger than the green bearings.

I would think that there are eleventy-million other things you can concentrate on to improve your van before even considering rear discs.
As mentioned, a properly set up system will concentrate 3/4 of the braking at the front.
Also, I'm not a big fan of 'green bearings'. They are not as good as the original bearings, and are only finding fans because A) they are sealed, so no maintenance. B)cheaper and foolproof, no adjusting. C) they allow disc conversions easier, since there is no more end-play.
The Hotchkis Challenger uses them for the disc conversion. They beat on the car very hard. However, they also have to replace the bearings a few times a year.
In a street van application, they probably wouldn't wear out any faster than the stock stuff, if ignored. So to me, there really isn't a reason to go with discs or green bearings unless you are exploring the limits of your vehicle regularly, and you shouldn't be doing that on the street. So how often are you taking your van to the track?

I have drums on the back and scarebird conversion disc on the front and it stops great, I don't think theres a need for rear disc, jmo,

And on the ther side if you did the rear disc you should never have a rear brake problem again including adjusting or replacing leaking brake clynders. If you building a show van and Iwas judging it i'd give more points for the disc than a$500.00 dollor chrome grill, or items bolted on ,It's your build so enjoy the fun of doing it your way...

Dix .... I have heard some interesting information concerning the green bearings on the rear. I realize that they stop the end play to allow for proper disc operation on the rear, but I have also heard that they can not handle the side load during cornering like the OEM bearings can. I have been lead to understand that they are fantastic for drag cars, but may not be so hot on the street. Have you had any issues with your vans?

Yes what you are saying is to be true BUT that is what Rod was saying, BUT under normal driving conditions you should not have a issue, It may be different if I was doing power slides and such, We have at least 5 of us running them, pickup's and vans with no problems yet. If you are going to convert to rear disc brakes this is the only option at this time. And that is the direction I will be going SOON the bearings have been in for 2 years now. the green bearing is a round or ball bearing. the factory is a roller bearing, The 5 of us do shows /van runs cruises camping, and such But none of us are ever Overloaded with weight, In other words none of these 5 are used for work, Hope this helps.

Dix, ball bearing VS TAPERED roller bearing.
As I said, "In a street van application, they probably wouldn't wear out any faster than the stock stuff, if ignored." While I didn't predict how soon that is, I'd guess that a van that is a secondary vehicle would never wear out either one if not subjected to something that would damage either one. In other words, if you replaced the bearings properly and used the vehicle lightly and only occasionally, they would both last for the time you owned the van.

Rod I agree 100 percent with all your statments , And sometimes I fail to wright what i ment to say,
No disagreement intended by either of us that i'm aware of