American Autowire Complete Wiring Harness Classic Update American Autowire Complete Wiring Harness Classic Update Kit for 1965-1966 Mustangs. The Classic Update Series is a complete wiring system in a box, giving you everything you need to modernize your classic Mustang's wiring system. Allows for most aftermarket accessories such as: gauge packages, heat and air conditioning systems, power windows, etc.4/5(14)MSRP: $859Brand: American AutowirePrice: $773.1 1965 Mustang Wiring Harness | eBay Gearhead 1964 1965 1966 Ford Mustang Wire Wiring Harness Kit Direct From Iowa. The plugs for the steering column are also included. The column plugs will fit both early and late model GM steering colu..