Shudder/Vibe 25mph-40mph

First, yes i have searched and did find a perfect answer.

Its a 1993 XJ with 243xxx miles. I recently installed a Rustys 3in lift. Since then it has a new vibration.

When taking off from a stop, a shudder/vibration starts as soon as i hit 25mph, stays till 35mph and then slowly fades out at around 40mph. I can feel it in my seat and floor and hear it rattle my center console. Other then that, there are no more NEW vibrations since the lift all the way up to 85mph.

I pulled the rear drive-shaft. The u-joints feel to be in good shape with no play. The slip yolk splines looks to be in great shape.

I did install a 1" transfer case drop.
side note
immediately after i got done installing the lift and before i had the tcase drop on, i tried driving it around and it made a clunking ticking noise.

Another thing to note is i had previously thought my motor mounts were bad because my engine would move forward and hit the fan shroud under heavy torque. It no longer seems to do this latley.

What do you guys think?
*Bad U-joints?
*Needs a slip yolk eliminator?
*Bad motor mounts?

All three of the above... OK, OK, you can get away without the sye with 3"... but the transfer case drop basically put the engine on a little bit different angle, so the motor isn't in line exactly how it was before. Hence not hitting the fan shroud anymore... the ticking and clunks without drop installed could very well have been the driveline. Best insurance would be to replace the u joints anyways, with some that you can grease. Which brings up a question for you, when was the last time they were serviced or changed? Answering that would let you know if its necessary.

Also, is the pinion angle good on the rear axle after the lift?

I have never changed any drive-shaft u joints on it. i got it with i think 228000 miles and its at 243500.
Would using cheap auto zone joints be sufficient?. i don't wanna spend good money on good ones if it doesn't really need them.
also, what is the best way to check if the motors?

i never checked the pinion angle. Dosent sound like something id be good at.

I've got the "heavy duty" checker (before oreilly bought them) u joints in my driveline, they got bought out what? A couple years ago? No problems here, they were like 18 a pop if I recall

Well, i just got done Replacing the u-joints on the rear shaft.
Its kinda hard to tell, but i think its still having the issue, only it seems to be less noticeable. What do you guys think?

I just took the jeep for a drive, withOUT its rear drive shaft.
While driving it in front wheel drive, the vibration is GONE.
So i see this as it needs a SYE.
Hows this: http://www.performanceoffroadcenter.com/oscommerce/product_info.php?products_id=153

and i want to run a front shaft in the rear.
Is this what i want? Cheaper anywhere else?