No need to Number them, everything is a different color wire, such as nitrous selnoids is all brown, fuel pump stuff is all pea green, and so on. They are either solid color, or have some kind of stripe on them. Other then grounds and power.
I do have a drawing of all wires to where it goes though. I will have that in the trailer for easy problem solving if something ever did happen.
I was going to buy a heatshrink label deal but they are kind of pricey. :P