Your LX470's factory nav plays DVDs. You can add monitors for your passengers to watch also, by tapping the video.

1) Take a regular RCA cable, cut off the connector on one end.
2) Separate the longitudinal braided wrap (aka outside conductor) from the center.
3) Run the outside conductor to a ground
4) Connect the center conductor to a wire tap connecting it to the red spotted video cable on the back of the unit*.
5) Run the cable to the video screen.

The signal is weak; you may want to add a video amplifier.

* The nav unit has 4 connectors on the top of the nav unit. Video is the red wire with gray spots (no line on it either) on the right most connector when facing the front of the nav unit, i.e., closest to the passenger side.