When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
The option the dealer has suggested to me is see if the video cable from the navigation to the screen can be split and if an additional video input can be added that will be controlle by a separate switch.
Actually I can't believe that the Mark Levinson system has no connection. I saw the IS in Japan has standard TV on the screen.