Yes, the switch box has two composite video inputs, plus the input from the stock NAV box. It has an output to the screen. It requires power and a couple of simple inputs to select which video source gets to the screen. The factory nav controls are used to adjust the screen brightness and contrast; I am not sure if the nav box is involved, or if the wires are just passed to the screen for this control. Also, if you remove the nav electronics, you will lose your left front speaker, so removing it will require some thought to keep everything working. You are probably better off to just leave it, even if it is not used.