i find it hard to believe that mine isn't already wired when everyone swears up and down that all of the '05-'06 models had it. from what i've seen/read, this is the only place the plug is located and it's not there for me. it doesn't even appear as if it's been snipped/cut off.The unused connector in the engine should be easy to recognize if there. Driver side fender, midway up, and is one of the connectors with the little red locking clip.
If you are sure what that looks like, the speed-o on the back of the transfer case, the fuel pump on near the gas tank, the hard top harness, and the cruise control may be the only red locking pin harnesses in the TJ.