I heard a new "chirp" a couple weeks ago and crawled under my 87 Samurai to check the u points. They seemed to be ok. Now I am feeling a slight vibration and a slight clunk when going from forward to reverse and then from reverse to forward. Can someone tell me how to identify this problem?

Disregard, it's a u-joint on the transfer case end of the rear drive shaft. Done that before on my old Sammy. I have 2 u-joins on hand. 

A special note here: It appears that someone used red loctite and an impact wrench to tighten the 4 drive shaft bolts to the rear end.
There was no way I could get them off with hand tools. Liquid Wrench didn't help. A propane torch didn't help. I had to cut through the nuts (and bolts) with a dremel to get the nuts off. . 

That certainly seems excessive.