With the detailed information provided by Gary, this servo would be used in conjunction with this regulator:
E2AZ-9D757-A
https://www.ebay.com/itm/Ford-NOS-part-E2AZ-9D757-A-dealer-installed-speed-cruise-control-regulator-/331714175935
https://www.ebay.com/itm/Ford-NOS-part-E2AZ-9D757-A-dealer-installed-speed-cruise-control-regulator-NEW-/112848319605