The PerTronix Ignitor and Ignitor II have been around for more than a decade. They remain the best single modification you can make to a classic Mustang. The Ignitor hides nicely inside an Autolite or Motorcraft distributor. It installs in 30 minutes. And it improves starting and drivability. If you're running a PerTronix Flamethrower coil, remember to bypass the pink factory resistor wire from the ignition switch. And always remember to keep your distributor's ground wire connected.