Wiring Harnesses for Classic Chevy trucks and GMC trucks Wiring harnesses, wiring harness clips, and obsolete parts for classic Chevy trucks and GMC trucks from Classic Parts of America. Chevy Truck Wiring Harness | eBay (1) 1970-72 Chevy Truck Front Light Wiring Harness for Trucks with Warning Lights. (Photo for display purposes only, actual harness may differ slightly). This is a NEW, never used harness. Give us a c..