Hitch Wiring Harness for an "04 King Cab, long bed?

I looked at courtesy parts and it was $127. I put one on my 2002 and don't remember it being a full body harness. I recall unplugging a connector and putting this in between. The harness the dealer is looking at is from front to back.
Don't buy one that requires cutting wires.

Clint

I think I'm going to buy a Curt Class III hitch off eBay from an authorized dealer ($167 including shipping vs. about $220 at AutoAnything). Probably go with the Dealer's wiring at $127. The guy at the Dealer thought it was wired to the back of the truck already (and you just ran a short harness) but I went out and looked and didn't see wiring except for the rear lights.

When I put a class three hitch on my old 99 Frontier KC, I bought a wiring harness for around $40 as I recall. I simply plugged into the taillight wiring harness and worked like a champ. You unplugged a connector on the taillight harness and inserted the new one. Took like 5 minutes to install. No wire cutting or splicing. I think I got it from one of the big box auto parts stores (Autozone, O'Reilly's, NAPA, one of those)

Awesome. I'll check with them first. They can usually show you how to do it.