You don't REALLY need it. A slim 10 mm open end wrench and a long standard screwdriver will suffice.
( And don't forget that you will need a 6 mm hex wrench [ or a T40 star wrench ] for the rear bow latch - this did NOT come with any roadsters, obviously an oversight on the part of MB / Chrysler )

Or you can get a combo tool # 129 581 00 66 from :
Mercedes Tools - Mercedes Benz Special Tools & Repair Information-Tool