Look at the Milwaukee, WI CL for it. I pulled parts off the truck before they scrapped it, and know them well. It was an '89 4.0L 5 Speed 2WD. He's got the interior harness to the tail light connector I believe.
You could use an XJ harness, but you will have to add wires for length, and change the tails somehow, as XJ's have dedicated turn/stops, and our's do both.
Rob L.