Thank you for your answers. I followed the book and picked up the parts this morning. I think he charged me list plus for the parts, but I had them in one day and will put them in this evening. I went to a link on the MB webpage
http://www.mbusa.com/brand/container.jsp?/heritage/expert.jsp&menu=6 and called the 1-866-622-5227, and they looked up the part numbers for me. The guy at the dealership was a real jerk, and wouldn't give me the information.
Are there parts books out there with the part numbers in them, so I don't have to research the parts numbers?