87 GMC Sierra 350 TBI. When I bought my truck, previous owner said the fuel tank selector switch was bad, only had to swap wires behind switch to swap tanks. When I removed the switch, to replace it with the new, the socket it plugs in to looks "flashed over". An electrical arc has at lived in there for a moment, how can I get a new socket the switch plugs in to, without finding a spare wiring harness??? It's not in LMC truck. Thank in advance.