Cost of re-wiring a FJ40?

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Aug 21, 2012
Dayton, Nevada
I know a guy who has asked me if I would be willing to rewire his '74 40 series. The truck had a Painless kit installed by the PO at the same time the engine was converted to GM EFI.

It's a mess. And by mess, I mean like using a residential junction box to house the fuse panel, mess. Wires everywhere... crimped splices and terminals with shoddy e-tape all over.

I told him the easiest way to fix it is to start over with a good used factory harness and add the components necessary to run the EFI rather than using another Painless harness.

The thing is, I have no way of knowing what a fair price would be to do the work.
I don't want to charge by the hour and am hoping to just name a fair price for the job. I'm pretty comfortable with the FJ40 wiring since I just completed my 3FE conversion.

ALso, his truck is a 10/73 build so I'm wondering what year range wiring harness would work well for this job?
If your time is free...

A new harness is in the $300 range. You need lots of heat shrink and connectors, so likely $500 in supplies.

With a V-8, there is no way a factory harness would be easier or better. I'd go with new.

Then it takes hours of time.
Ask "Coolerman" for a quote for a new harness. He's the specialist on this.
He also has all the connectors and stuff that you need.

the Painless harness is geared towards domestic engines, why not work with that given that he has a V8? also, if he doesn't have a lot of the OEM switches, there is less benefit in using an OEM harness

time is indeed the most expensive part of rewiring
Sometimes it is easier and cheaper to fix a "mess" than starting over with something you don't completely know about. With a GM EFI and a '74 cruiser, there is no wiring kit that is going to do the job, so it will either be completely custom or a hybrid of GM engine and Toyota harnesses. You have to ask yourself what is wrong with it. Looking ugly doesn't count for much and can be corrected relatively easily.

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