[72_ChevyMan]

Can anyone tell me the size of the wire they are? Like when it says 18 by the name on the diagram is that the size of the wire? If so 20g seems way to large. I'm wanting to rewire the entire truck with just wire (have some custom things I want to do) instead of buying a kit. I just cant find what gauge of wire I'm needing to buy and what gauge goes where. Thanks