1968 Mustang Wiring Harness | eBay Part # 20121. Painless Wiring. This 22 circuit direct fit 1967-1968 Mustang harness has many of the factory connectors already installed on the harness out of the box. 1968 mustang wiring harness | eBay www›Search›1968 mustang wiring harnessFind great deals on eBay for 1968 mustang wiring harness. Shop with confidence. Skip to main content. eBay Logo: Mustang Tail Light Wiring Harness Fastback w/ Sockets 1968 Alloy Metal Products See more like this. 1965-1968 Orig. Mustang GT Emergency Flasher Switch & Wiring Harness Nice . Pre-Owned. $74.