Originally Posted by Curious Joel

We all know how difficult a nav retrofit is on an X5, or any BMW for that matter....

Well, my friend drives an '03 M-B ML320. They ordered it without nav. A few weeks ago they decided they wanted nav. They took the car to their dealer (Mercedes Benz of Princeton in Lawrenceville, NJ) and they just put it in! How can it be that simple? Granted, it already had the screen from the COMAND system, but you'd think they'd have to do all sorts of wiring. I'm guessing the car doesn't come pre-wired for nav...