Replace steering rag joint with urethane

At 151,000 miles, my '96 Jimmy's sloppy rag joint has finally driven me to find a better solution. I've checked out and attempted to convert to the U-joint intermediate shaft from a '98 Grand Cherokee as has been heralded in this forum elsewhere, but found the upper end of the new shaft to be too large for the small double-D end coming from the firewall. Oh well.
My new thought is to fabricate a new rag joint from a thick sheet (1/2") of hard polyurethane (Shore 90-95A hardness)...the same that is used in performance suspension bushings. I'd cut the rivets, slip in the new disc, and bolt up using new hardware.
My questions are:

1) Has anyone considered this before and if so, what were your results?
2) How does the intermediate shaft come off? I can see the lower clamp that attaches it to the steering box, but the top is covered by an orange rubber cover. Does the lower half collapse onto the upper portion and then it slips off the steering column shaft? Please clarify.
3) If this works, would anyone be interested in purchasing them?

Thanks in advance for your help and input!

The upper end of the grand cherokee shaft (female) is to big for the shaft coming out of the firewall (male) ???? WTF.... I've done 3 of these now for other people outside of myself (so really 4) and every single time the steering column portion was smaller than the grand cherokee intermediate shaft hole and we had to dremmel out the grand cherokee shaft...

Well, unless the used parts place I got it from pulled it from a different Cherokee (I did specify a '98 Grand Cherokee). I measured with calipers and it was at about 4-5 mm too big in the wide dimension and even more across the flat dimension. Kinda wish I had taken pics of the shaft before returning it, but oh well. The ends weren't the same as in the pics shown in this forum. Instead of being cast/forged and appearing bright finish and round, they were painted black and formed from sheet steel. That's what I had to work with. And thoughts on the original questions I posted?

Sounds like you got a Cherokee not GRAND cherokee shaft (your description sounds like the regular cherokee)

That said, to your original question, Considering the amount of travel that the intermediate shaft uses, I would think it would eventually break apart...(then again, I'm no poly expert)

I guess I'll fiddle with it a little and do some research. Am I correct in how the original shaft can be removed? Plus, I would like to know the size of the rivets that hold the original piece together (the part that actually goes through the rubber disc) so I can incorporate that into my design. Thanks for the good help so far!

I for one would be interested in any results your research turns up. I had a thought to attempt to replace the old rag joint material with fresh material if its available somewhere. I haven't looked very hard. The slop would come back eventually just like an oem replacement, but I could live with another 180K miles before the next change.

I just got an e-mail reply back for gmpartsdirect saying the oem shaft for my 95 is no longer available. So that removes the easy install but expensive solution.

Not sure if I feel brave enough to perform rlith's conversion.

aperently they make rag joint rebuild kits ... http://store.summitracing.com/egnsearch.asp?N=400016+315605&autoview=sku only $12.69

Good knowledge to have, thanks. I didn't want to slap in the same old mushy disc. Rather, I wanted to get a little more steering response. I am looking to use a harder material that is still flexible enough to cope with the slight angle between the steering box and the intermediate shaft. I may buy it anyways if only to have a pattern/back-up and the hardware to use. Thanks for the info!

(Edited 17-Jun-2006) I've measured the disc in my truck and it appears to be smaller than what is in this kit. Mine is 2-1/2" in diameter while the kit has a 3-1/4" disc. So, nix the pattern idea. I'll just have to cut it apart and backwards engineer it. More details to come...

After much delay, I fabricated a new joint from 1/2" thick Shore 95A durometer black polyurethane. It was not doo difficult having a drill press. I started by clamping the poly sheet to the base and drilling the inner hole using a 3/4 hole saw. I then used A 2-5/8" diameter hole saw to give me the proper 2-1/2" outer disc diameter. One side of the inner hole had to be countersunk to mate with the metal plate. Then marked and drilled the four holes, making sure they were aligned with the disc center and 90 degrees from each other. I used M10x45mm flared head bolts and the holes are just large enough. If I can find a site (or get a recommendationfor one) to post pics, I will do so.

I've noticed slightly better feel, but I now have found that most of the slop is in the steering box itself...not looking forward to replacing that...ZQ8 anyone?