I've seen this done on a 5 series using an RGB converter as shown here. http://www.tvandnav2go.com/bmw-tv-navigation.html Supposeably they offer one for the 04 7 series. This used an auxiliary input for sound in the 5- but the aux in isn't offered- at least by BMW for the current 7 series- so I'm not sure how this system is wired- I haven't seen any 7 series with an IPOD or Sirius unit installed as of yet. Not to say it can't be done.... but if it can be- it's rare. The main concern is the 7 series relies a LOT on fiber optics for the stereo and display system- so if anything happens with the fiber optics- something added or removed- it can take the entire system down. Also- if you want the dealer to work on the car- warranty or programming- all of the items must be removed before programming as programming of the car also takes place over the same fiber optic lines. Hopefully this helps you out in your search.
--Cliff
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