Here is Ford's step-by-step for pulling the motor. If the plastic cable is broken, you will need to pull the motor apart and remove the broken part of the cable.
Antenna Motor, Electric
Removal
1. Lower electric antenna (18850).
2. Remove retaining screws of RH front wheel splash shield for access to antenna lower retaining screw.
3. Remove lower retaining screw.
4. Using appropriate fender protection, unsnap radio antenna base cap (18A927) from antenna base and remove.
5. Remove radio antenna nut (18865) from top of motor tube and remove electric antenna through fender/splash shield access.
6. Disconnect radio antenna lead in cable (18812) from electric antenna.
7. Disconnect motor wire connector from electric antenna.
8. If a section of plastic antenna cable is to be removed from antenna motor:
Remove the four attaching screws, drive mechanism cover and drive mechanism.
Locate and remove the broken piece of cable.
Install the drive mechanism, drive mechanism cover, and attaching screws.
Installation
1. To install, reverse removal procedure.
2. Tighten top radio antenna nut 9.5-10.5 N-m (84-93 lb-in).
3. Tighten lower electric antenna retaining screw to 5-6 N-m (44-53 lb-in).