Randy,
You will need to get the driven gear also if you don't already have one. As for getting the cable for a Mustang, they may be a little longer or shorter than you need. They make a universal cable that you can tailor to fit about any length and they can be found in any good auto parts store. And the Mustang cable may work length wise. You could always take something flexible and run it the way your cable is going to go from the speedometer to the tranny and then measure the length of it.
Ron
