Wiring diagram, any standards?

I am about to start planning the wiring loom for the car excluding the engine wiring that will be a separate loom directly from the engine management system.
Any standard looms documented that i could use as a starting point and modify to get a complete picture? (Looms for gt40 replicas that is)
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If you're using a modern ignition system, you probably should look up manufactures information.

If you want to follow the British Standard wiring colors, take a look at an article such as this one (first I found on Google) http://www.expeditionlandrover.info/Lucaswirecode.htm

In the 60s, Ford published a series of papers with the SAE on various topics about the development of the GT40, one of them was on the electrical system. It includes a photo of a huge board with the entire wiring loom laid out. It also has a wiring diagram.

You can find a link to a PDF of the papers at: https://www.gt40s.com/threads/original-gt40-sae-papers.23911/
Page 66 shows the wiring diagram, page 67 shows the wiring loom.

The rest of the papers are an interesting read. My favorite illustration is on page 5. It should a diagram of the Le Man track with the speeds and gears at the corners and straights.
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I managed to get a hold of what i was looking for.
Now i am wondering what lucas switches are "standard" for a gt40 replica, what partnumbers should i look to use?
I took the complete loom of a Ford Fiesta mk1.
It realy comes with all the essentials including a fusebox.
Its easy converted to rear engine with just swapping the front engine loom to the back.
Also easy converted to toggle switches.
Very easy to trace as all the wires come collorcoded and schematics are easy to find in workshop manuals.
Paid £50 for it 3 years ago.
Does anyone know who the user Ian Cowan is on this forum?
I need to come in contact with him to ask some questions related to wiring diagrams i have snatched up.