Snow plow wiring harnesses are available for purchase at PlowPartsDirect and Smith Brothers Plow Parts as well as at Amazon.com and eBay. Different brands and models of snow plows require different wiring harnesses.
Smith Brothers Plow Parts also makes available wiring diagrams for several models of Meyer snow plows and explains the differences to help consumers buy the correct parts. While many people prefer to save money by buying used snow plows, often parts aren't available for older models. CentralParts.com provides a handy list of snow plow brands and models with explanations of the differences and the various mounting and wiring systems that are difficult to find.