Should be easy if you have the connector in the console--top part. (it could be covered by an easily removable plastic cover, which is removed by prying at the indentation on the wider side.)
If you want phone charging by the vehicle, the best bet is to get the "cradle" for your phone and just click it onto the connector.
I believe this still has to be ordered from the UK (easy) as USA dealers don't have it.
There are two version--one with a wiring pigtail to allow connection of the iPod system and one without.
Both are shown on this page
Comand Online Ltd :: Mercedes Phone/Bluetooth :: Cradles & Bluetooth Adapters
This cradle is convenient as you have the option to put phone in cradle or not. Obviously putting in cradle gets you charging plus use of car's antenna, but otherwise all the phone stuff works the same.
Once the phone and the cradle are paired (one time only) it works just fine.