I've done some work with Ford vehicles equipped with Sync and its close to impossible to install Sync in anything but a Ford, Mercury or Lincoln.
Sync relies on information from the vehicle's on-board communication networks. Sync and other vehicle electronics modules are programmed to the specific vehicle they are installed in. Programming includes vehicle specific network messages, module configuration and the vehicle VIN number.
To complicate things, every Ford is different. For example, a Fusion generates network messages indicating the status of the instrument panel illumination dimmer level out of the Smart Junction Box, yet a Crown Victoria generates the messages out of the Lighting Control Module.