Help wiring for Eaton 2 speed axle - The Stovebolt Forums Jul 25, 2012I found a new switch on eBay, but no wiring diagram. Wires are in 3 different sections/pieces none of which are connected. Anyone have the diagram to wire up a electric shift 2 speed. Circa 1952. Thanx, GMCPicForums · Big Bolts · Active Threads · Whos Online 14520 - 1970/1971 GMC Truck Full Colored Wiring Diagram 14520 - 1970/1971 GMC Truck Full Colored Wiring Diagram If you're tired of trying to read and decipher cryptic black and white wiring diagrams out of your old shop manual, this wiring diagram is the solution.