Frank,
Is that original then, they had no colour coding, or has someone changed stuff over the years..?? If you used colour coded cable it would make rewiring a lot easier. You would need to make up a printed record of the codes to go with the car (Electrical Schematic Codes), you can do that on the PC. I can get you rolls of cable at trade in various colours, you can also get now the super flexible cable, all you need is the core diameter to give an idea of the current handling and decide what coating, ordinary, smokeless etc. and off you go. Then you just need a thick flexible tape to wrap the new loom and all done.
Cheers
R