I can understand where you are coming from, but...............................................
What happens to the guy that makes/takes the time to do the harness and someone who doesn't have the general knowledge to add air to the tires tries to do the swap, and ends up totally FUBARing their rig and sues the harness maker? Or they order the harness, he makes it, and then they back out after looking again at a swap they should have never even thought about? Its a good idea, but there are somethings that people need to figure out on their own. I have done a 302 swap in my own 84 Ranger and I used things that others didn't. I used a C-6, most don't. I used Holley Pro-Jection, most either go EFI(for crawler/trail pig) or carb(street/strip). To many variables to a lot of swaps. I understand your talking about the 4.0, but sometimes things aren't always black and white.
I was thinking (which I dont do to often) with the demand of everyone doing a 4.0 swap to there trucks. From what I have read is that its mainly usen the harness out of the donor vehicle maken a few mods to it and then pretty much plugging it in and buttoning it all up. Some one who has already done the swap a few times should be pretty good at doing it and doing the harness for it. Youd think someone would gather up a few harnesses to start with and repin them and get them pretty much ready to go and make a direction/instruction sheet looking at there own truck and selling them to people whod like to do the swap. I know in my opion and 5-6 people ive talked to that want to do the swaps had asked if I knew of anyone who would be interested in maken the mods to the harness and all so when it was time it was pretty much just bolt in hook everything and maybe have to make a change here or there that couldnt be done with only the one harness and being done. Its just a thought but it seems like it could be a decent little profit for a side job. Or am I just thinking off the wall again and should just shutup and think of something else. LOL 
and try not to think lol thanks guys
I don't think like ANYBODY else!
