wiring harness

[Fo-Mo-Co]

The harness in my 68 has a d1 tag. it also has a burnt large yellow wire from the ing switch to the fuse box. i also have a 71 parts truck with a good harness. it should be a d1 harness also. did they change these harnesses during the bump era?
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[fordman]

yes there are several Wiring looms for these trucks. they are mainly the same but some have small differences. such as the plug for the instrument cluster. 67-69 uses one style 70 uses two styles. one for gauges the other for no gauges. 71/72 plugs are similar to the 70 plug as they have two styles with or without gauges. then there is the camper specials. some of those harnesses are slightly different. there are also looms with and without extra fuel tank hookups. door switches can be incorporated in some wiring looms while others have none and i once saw one that had the loom added on. like maybe it was a dealer add on option or something.

the main thing to look for is the correct instrument cluster plug. if it is the same you can swap only the interior cab wiring harness. if it is different then you will also have to use the passenger side inner fender wiring harness with the main cab wiring harness. one quick way to tell if it is with or without gauges if the instrument cluster is gone. is to look at the three plugs coming out of the firewall on the passenger side. if all three plugs have are square then it is for gauges. if two of them are square and one flat then it is for dummy lights.

[mk]

You can swap in that '71 dash harness as long as you use the '71 cluster and L&R engine harnesses as well. The key is mainly matching the cluster to the harness like Craig said. The front harnesses connect inside the cab from 67-69 and in front of the firewall from 70-72. You're actually improving the electrical system by using the newer harness; getting a fuse link protected alternator circuit, door light harness built-in (70-72) and the parklights will stay on with the headlights too. The emergency flasher switch plug will be in a different location closer to the main cluster but you can either extend the wiring or move the switch under the dash by the column.


mike