Vibration at 55+ and yes I did some searching

So, finally got to drive my 99 Cherokee after months, yes months of work.
What you need to know, AW4 to NP 241 (rubicon transfer case), new tom woods drive shaft, Ford 8.8 with about 70k, 33" pro comp on rock crawler wheels (balanced), TnT long arm kit.
At freeway speed I get a constant vibration and it almost droans but you can really feel it in the seat. I took the jeep to a driveline place and they said it could be because the 8.8 has a offset differential and that has caused another angle. My friends have wranglers with this swap and the driveshaft is half the length and they do not any problems, so I doubt that is my problem.

If you are familiar with the NP 241 there is a big balancer on the output. I have a feeling that it maybe off a little and that is causing my vibration. Any suggestions? The transfer case would be a ton of work to get out so that is really the last thing I want to do but I will do it if someone has some insight of what the solution would be.

Also, my front yoke on the transfer case is leaking ATF. Anyone have some ideas of how I might address that?

Pull the front yoke and replace the seal.

I seem to recall that the 241 output can be removed and replaced with a front output to reduce those vibes

Heres the article from JB conversions website on the "balancer that comes out the back of the t-case, Usually, a 55mph vibe is from a bent wheel, incomplete tire balance, or slipped belt, but in this case it just may be the balancer from the t-case, let us know. thanks, good luck.
here the site. http://www.jbconversions.com/pages/products/nvg241OR/index.html

pull the front d-shaft, see if it fixes the problem.

I do not have a front DS.
I brought the jeep to both a ds shop and a 4x4 place here in spokane. The ds place was virtually no help. The 4x4 place had some ideas and was willing to look at it free of charge which is always nice.
Unfortunately, the 4x4 place was not able to quickly fix the problem but they did pump some grease into the slip yoke of the new tom woods ds it seems to have helped a little.
I did talk to John at JB conversions and he said that the transfer case was unlikely to be the transfer case. So still nothing fixed but seems a little better. I will check back soon.