Yeah I gotta agree wit ya Richard, these old trucks started fine from the factory back in the day with #2 conductors, so really how much bigger do you really have to go for an improvement? I assume you're using a round cable for your ground in place of the braided style cable? As I said, I've never see the braided cables anywhere, larger that #2.
There is a truck parts house next town over, I thought I might stop there one day and check see if they carry any larger cables. Probably not because most of those electrical systems are either 12v or 24v which really reduces the size of the wire used and smaller wire means less weight which translates into more payload.
DG
