Thanks for all your suggestions. I looked into this a couple of years ago, and ended up using Express PCB, which I thought was pretty good. The only real problem was the time it takes because it is designed for 1 page designs, but the page is too small for a whole car.
I have attached the work I had done up to that point. It is nowhere near complete and probably has errors, but if you are also looking it gives an idea of what you can do with it.
I also tried PCB123 at around the same time without success.
I have now tried to use the demo of Visio, and also SmartDraw, but couldn't find anything remotely as sophisticated as ExpressPCB.
Peter D - I'd really appreciate your wiring overview please. PM sent.
AutoCAD Electrical and Altium look to be way over the top, jsut to be able to draw a car diagram.
Last car I did it by hand with pencil. 1 page for front bulkead forward, 1 for dashboard, 1 for middle/ rear of car, 1 page for the clips. (or something like that) I think I will have to do the same again unless anyone can come up with a more suitable program.
Anybody know what Haynes use for the diagrams in their manuals? Or are they supplied by the manufacturers running Altium/ Autocad?
Edit : attachment now added