We went with a standard chip from Hypertech that was a direct plug-in for the '93 auto-equipped 5.0 Mustang (PN 693111). Installing the chip requires removing the passenger-side front kick panel, loosening a few mounts, unplugging some harness connectors, and removing the stock computer. The Hypertech chip plugs into the computer's factory "service port" after first removing all the protective grease on the port terminals. Because the Hypertech chip is smog legal, there's no need to remove it when it comes time for a smog check. If your car is a different year or model than our test car, or if it's modified, Hypertech likely has a chip for your application.