Meyer Plow Main Harness Wiring Pin Outs - Meyer Snow Plow 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 snow plow wiring harness | eBay 1 product rating - meyer snow plow light wiring harness 80831 & switch- new made by truck-lite atl. $94. guaranteed by sat, new meyer snow plow wiring harness for chevy part # 07402 (part of 07400 kit) 2 product ratings - genuine meyer snowplow plow side wiring harness weather cover 22263 - for 22262. $14. fast 'n free. buy it now.