Welcome to the Bolt, John.
I don't have specific answers to your questions but found a couple of resources that you may decide to refer to from time to time.
An online 48'-51' chevy truck manual (has the wiring diagram with wire sizes and wire colors)
http://chevy.tocmp.com/1948_51truckshop/index.htm A service bulletin from 51' on the Rochester B.
http://chevy.tocmp.com/Rochester/index.htm Both of these are from the Old Online Chevy Manual site. Lots of wonderful info there.
