I too have been considering exactly this. Please do post up your results.

 

I had this this spring, turned out to be a u-joint just starting to go bad. Didn't have much play but when I popped it apart was full of rust. Did both and it took away probably 70% of steering wheel vibration. I have a feeling the rest is due to lack of SYE or possibly front driveshaft. But with a 242 I wont be able to get a SYE anytime soon.

 

You can get a 242 or 242HD SYE from Tom Woods. He is the exclusive distributor for AA 242 SYE. I would try using a spare front driveshaft instead of buying a complete package for the rear. I have had some front vibes from worn carrier bearings in the front axle. After I rebuilt the front axle the problem went away. Could also be the driveshaft. You could try removing the driveshaft and see how it changes the vibes. Pinion angles, u-joints, and centering ball should all be checked. With two driveshafts spinning at high RPM, they can actually phase up on each other. Your front doors can be vibrating because your rear driveshaft has a problem.

 

The hack-n-tap yoke for the 242 and 231 is $70 from Powertrain Industries. Or get the whole package from IronRock. Yoke, tap, bits, and drill jig.
I have had one for almost 4 years now.

 

UPDATE: I have installed new Cooper AT3's. These tires are awesome! I went from the tire shop straight to Pleasant Mountain. This trail tested these tires to the max (deep mud, steep granite slopes, mountain rock slide deposits, tight corners). SteveMongr excellent recommendation. The pulsating vibration is lesser but still noticeable around 60mph. Im installing the SYE and rear leaf packs tomorrow. I'll keep posted.

 

UPDATE: The AA SYE and RE full leaf packs are in! Vibrations are history. While doing the project, I noticed the front passenger U-joint was bad which may have been a contributing factor to the vibrations. However, the SYE is in and it feels good to have that done and in the rear view. The RE full leaf packs ride much better than the cheap RC AAL's. The jeep is sitting pretty netting just over 5'' of lift. Looks a little goofy with the AT3 31's but I'm laughing all the way to the bank with what "decent" gas mileage they are giving me (15mpg on a great day). Thank you to all those who gave input to this tread.