MeyerPlows - Meyer Plow Main Wiring Harnesses Info Meyer Plow Main Harness Wiring Pin Outs. These are the "1 Piece Plug" and Universal Wiring Harnesses. The 1 Piece Plug made its debut with the MDII Mount. The MDII made it necessary to unplug EACH plow light, the 3 individual Coil wires, and the Motor Harness to remove the complete plow assembly. Meyer came out with the 1 Piece Plug. meyer wiring harness | eBay 2 product ratings - MEYER WIRING HARNESS FOR SQUARE PAD CONTROLLER. $67. Guaranteed by Thu, Jul. 18. Buy It Now +$15 shipping. NEW MEYER SNOW PLOW WIRING HARNESS FOR CHEVY PART # 07402 (PART OF 07400 KIT) See more like this. Genuine OEM Meyer Snow Plow Truck Side Wiring Harness Weather Cover 22261 22279.