If you get hold of a copy of the original vacuum/wiring diagrams it shows how to set up the factory unit. There were two different systems, one dealer and one factory installed for 67. The 67 is harder to come by since items like the dash switch, under column wire tray and turn signal lever are 67 year only items. If you need more help send me a private e-mail and I can get you in touch with the guy who's literally writing the book on Mustang cruise.