I guess it depends how much time and money you have. I chose to modify the donor harness. It didn't find it difficult at all, just time consuming. I recommend getting the Ford electrical and vacuum trouble shooting manual before you start. Then just start cutting away. Worst case senario is you cut the wrong wire and have to fix it. I'm glad I did it myself because I have a better understanding of how everything is wired.
For Me Not a chance in a very hot place. The new harnesses are clean, give you the opportnity to trim as needed, and all the connections are as good as you make them. PLUS you don't have to worry about messing up or missing some wire here or there and when you have a failure, where the H do you start looking, through all those old wires. Just MHO
As always, your wisdom is an blessing to the rest of us . . . you are just soooo "right on the money" with all your posts and replys.
I (being an electrician) re-did the factory harness on my Cobra to "clean it up" a little. I shortened some wires and lengthened a few also, all in the name of clean.
I now have a very very good understanding of what is going on in my EFI wiring and feel very confident that I would now know where to look should there ever be a problem. This can only come from "hands-on" work. I know where every wire goes and what it does in the multitude of circuits needed to support EFI.
As for the rest of the car . . . Painless 8 circuit wire harness with some customizing to make a few things work the way I wanted them to work.
If you've got the time and patience (and a good book with pictures and diagrams) go for it. If you are the least bit uncomfortable with electrical work, get-er-dun by a pro or get a pro harness.
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