Adding Video input to Nav. System

["John R. Bell" <bell@xxxxxxxxxxx>]

Another post for the collective masses. I have a friend with a '98 540i.
He was wondering about getting another video input into the Nav System. 
Eg. He'd love to put a webtv box in his car hooked to the cell phone
along
with video being displayed on the OBD monitor. 
All he really needs to know is how to:
1) put video in 
2)turn video on (I don't mind if it works only when stopped).

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