if you use a newer harness the fuel pump will not work. it will have to be hard wired. when i convert for people i make them spend the 79 bucks on the granatelli harness . saves a ton of time and problems. keeps all the factory wiring so it is guarantee for everything to work. just my .02 but it really saves time and frustrations. i have converted over 20 cars so far and had zero problems using this harness. just remember to unplug the vaccum line from the map sensor.