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. classic truck wiring harness | eBay Find great deals on eBay for classic truck wiring harness. Shop with confidence. Skip to main content. eBay Logo: Shop by category. 4 product ratings - 1967-68 Chevy Truck Classic Update Wiring Harness Complete Kit 510333 . $539. Buy It Now. Free Shipping. 22 new & refurbished from $539.