[Bob Carriere]

They are practically the same ....... the early cab 11 did not have front fender mounted parking lights the cab 12 did...... not all cab 11 had night driving lights shining on the rear axle cover........ Canadian models of the cab 11 that never went overseas did not have the blackout system used in Europe....although many Canadian Cab were retrofitted......

So find and use the wiring diagram from the early cab11 / cab12...I was surprised to see you using my own cab 11 nightmare......field mice had eaten away all the insulation leaving bare wires everywhere. I basically took wire cutters and removed everything.............. but......... I was fortunate that some one made for me a perfect copy of the wiring harness, every connector, every color code and gauge respected with all bare wires already tinned ready for soldering..... and every wire was tagged as to its purpose.

It was a simple matter of taking one colored wire....look it up in the maintenance book and do the connection. The routing of the wires was simplified by examining two spare parts cab 12 trucks and when stuck asking as many questions as possible on the Forum. Some difference of opinion will occur on the location of specific wires and sometimes it is hard to decide if the sample truck you are using is "unmodified" by the numerous previous owners or done as a military modification. It leaves you to decide how you want you truck to be.

I am not aware of any readily available complete and accurate CMP wiring harnesses ........ it is labour intensive to fabricate so the cost his or would be high....... connectors and proper modern wiring with the original color codes are available for automotive restoration and are lurking on the web.....

I have converted, at the time of the wiring, to a modern 12 v. alternator which required thinking but not that complicated.....and added a rear axle light and turn signals as the wiring harness was built with the extra wires required at the time of assembly.

A lot has been said and written on the Forum and maybe we need a "sticky" devoted entirely to wiring cab 11, 12 and 13 Chevrolet.....and then you have the similar but different Ford cab 11, cab 12 and cab 13.......

I will try to help you out with questions and pictures........ you now see what I had to start with........ it is do-able...... just need to be patient.

The big SECRET is that Phil Waterman fabricated my harness..... one of 3 he ever made...... and have been ever grateful since.

Maybe the answer for future wiring snake nest is to document how to make your own using large plywood sheets painted white like the illustrations on Phil's web site and follow the diagram in the books. The big question is to arrive at the exact or near lenght of each wire before cutting it off the spool.
And to be economical you need to buy many spools and bags of fittings/connectors..... leaving you with enough wires/pars to make a few more... BUT be careful ......selling them may not be as easy if you try to recover you time and efforts some people will not pay the fiddler.

Currently I am aware that a full Dodge M37 wiring harness is around $1200 US........... that reflects the efforts and hand work that must be done to make and accurate copy........ oh and it comes with a multi page phamplet of instructions.

Grab your courage and wire clippers and go for it.

Cheers

Thanks again Phil!!!!!!!!!!!!!!