Topic: White vs Black & Red vs Blue Circuit Connections

[9F94M567042]

Hello All,
I don't know if this subject has been discussed prior, if it has, please point me to the discussion.
I have a 1969 Mercury Cougar. I'm pretty sure this topic would apply to Mustangs as well.
I would like clarification on the Black vs White 18 pin instrument panel connector as well as the Red vs Blue circuit board.
Did the Red board get the Black connector and the Blue board get the White connector or was it the other way around?
I have heard it discussed both ways but have never heard anything concrete.
Did it depend on plant or year or model? Any clarification on this would be very much appricated.
Thanks

[Coralsnake]

1969 Mustangs all used one wiring harness and one circuit board they were not shared with the Cougars.

I believe the Cougars change depending on time of production during the model year and model of the car.

[Mike_B_SVT]

From the WCCC parts page;

The red PCB (printed circuit board) was used in the latter part of 1969 (from 2/17/69 on) and all of 1970.
In 1969 if you had a white plug connected to the PCB it used a red PCB, if you had a black plug the blue PCB was used.

https://secure.cougarpartscatalog.com/c9wf-10c956-d1.html