Wiring a 4.0 into a fsj

[GWag89]

Roger that!

[Booth755]

I'm trying to use as much of the existing wiring as possible and the ecu will be in the cab under the dash to protect it from moisture.

It seems like it will be easier to use the fsj bulk head and wire the 4.0 harness into it. Mount the ecu under the dash and rout those wires through a hole in the fire wall. Use the existing wiring for the lights, horn, etc. And tap into the fsj bulkhead to power the 4.0 harness and ecu.

The only issue I have with that method is having 2 wiring harness under the hood! Both harness will need to be thinned down ...but until then I'm going to have a birds nest

If you have the time and money, get a painless wiring kit and redo all the wiring at the same time. Only way to really get a clean install.

We're would you get said wiring kit for a 76 j10 with a manual when I come home from deployment I'm putting a stroker in it

[GWag89]

What harness are you looking for? The 4.0 harness to wire into your 76? Or a new 76 harness?

[Stuka]

http://www.painlessperformance.com

[Cheap Hobby]

You may be able to get stock replacement harness for the truck from some fsj vendors. But I'd you want to upgrade to better larger wire you will have to use an universal harness and do the final light and plug install. The harness is ordered based on the # of circuits you want. For the price I would look at Rebel Wire much lower price and you won't be as worried about screwing up a cut. As mentioned above set the engine up up as a stand alone unit. You can combine the trucks few gauge wires in to the 4.0 harness everything else on the truck is small and down the drivers side for the most part.

If you get a complete new truck harness you can incorporate the power circuit for the ecu it the new harness. Then bundle all to your hart's content as you will be determining the length and route on the wires.