Fantastic write up! I joined just to give you your props! I was considering a 3rz in my 2nd gen v-6 5-speed Runner, but not any longer.

Especially helpful listing specific accessories from specific motor flavors...what to use and why.

Finally got a chance to install the URD short throw shifter today. They told me to order the same one that goes on a 3.4 pre 2005 and it should work. It did not work completely. The aluminum spacer block was not high enough and as a result the shifter lever would not move the linkage correctly. Could not get into gears 1,2,5, or reverse. After an hour of trying different things I noticed the problem. I had a local machine shop fab an aluminum spacer block that was .187" (3/16") thicker/taller than the one that came with the kit. Put this new thicker spacer in and it worked perfect with the rest of the URD kit.
The rest of the parts in the URD short throw shifter kit worked great.