just a heads up, i purchased part #999Q5-KU001 and changed parts out to accept a garmin 755T (traffic receiver capable), and then wired the car for it. After ridiculous frustration i discovered this dock DOES NOT fit an OR. you need 999Q5-KV001. this part is different than anything i have seen on this site. There is a small computer board and two external speakers built into the docking station, as well as a USB connector for doing Lord knows what... and the updated texture of the dock itself matches the radio control trim.
I ended up gutting out the little computer board and external speakers, and the traffic receiver tucked nicely into the dock where the chip used to be. the sound on the garmin unit is more than adequate. if i was electronically capable i might have tried to get it all to work, but i was already frustrated after mangling the old docking station which i can no longer return (which is now sitting on my desk).
But - if you are getting the Nissan garmin, or do not intend to use a traffic receiver then the new dock is pretty awesome since it has the new features. moreover this would indeed be a ~30 minute self-install if this was all you wanted. there are instructions in the box itself. guessing the dealer would charge you $75-100 if you wanted them to do it.