The navigation system is custom made by Pioneer for Ford. Since it is not a consumer unit, the Pioneer web site doesn't have a manual. The headrest DVDs are made by Invision, and are customized for Ford.
FYI, the navigation manual describes how to update with a new map DVD. When you eject the map DVD, the whole faceplate of the player folds open to reveal a special map DVD slot. I would not suggest even trying this to play a movie DVD.