The Classic Parts wiring harness (link in your first post) is hard to beat for quality and for the convenience you seem to be looking for. 10% of coupon is attached below. Their shipping charge is as fair as any vendor's.
The leads are numbered and terminated and the appropriate length for each original circuit in your truck.
It comes with instructions, but you will most likely find any harness a little confusing, especially routing wires from engine compartment through the dash and under the dash. If your present harness seems to be installed as-original, take a lot of photos before removing old wires.
It comes with extra wires, if you ever want to add a tail-light, change a few bulb fixtures, and add a turn-signal switch.
Finding/installing firewall/etc grommets is also a challenge for a first-timer (it gets a little easier after doing a couple of trucks).
