I just finished rebuilding one for a pick-up that I sold to my father-in-law, and I must agree that they are a Royal PITA to work on, but I pulled it, replaced all the gaskets and seals that I could without pulling the heads. I had never fooled with one before, but I got everything back together and into the truck and she fired up on the very first try. It is soo much quieter than my 22RE.
If you have the patience, they aren't that bad, just a lot of hoses in hard to reach areas, and I did cut several because I either couldn't reach the clamps or they wouldn't come loose, but other than that and the vacuum hose routing it is doable. Make sure the HG has been done, check the timing belt and water pump and you should be good to go.
I actually have another one sitting in the garage that I am going to be rebuilding soon to go into my 88 4Runner with a blown motor. I did some reading and alot of folks would tell me to do a 3.4 swap, but for my part, I don't want the headache of having to fool with the wiring and such, so I will just stick with the 3.0.
Just my $.02
Tucker