If your vehicle's main wiring harness doesn't have COP (coil-on-plug) trigger wires, you can simply upgrade to one of Holley's universal ignition harnesses. They're specially designed to install coil-on-plug or coil-near-plug coils on Holley EFI systems into Holley Smart Coil ignition sub-harnesses or GM LSx coil harnesses. These harnesses are ideal for use with Holley HP or Dominator ECUs, but are compatible with other EFI systems, as well. Extra pins are provided for both the metripak and ECU ends, if you decide to shorten the harnesses. Caution should be taken to ensure coil trigger wires are installed in their correct pin locations to prevent engine misfire. Make certain your EFI system fires right every time with Holley universal ignition harnesses.