I would post over on the Diesel Discussion - PeachParts Mercedes ShopForum as the Body is the same and there is a lot of People that know a lot over there.
You could buy a Service Manual DVD or CD Part numbers for service Manuals STARTEK
Star Service CDs and DVDs
Contact Consumer Promotions at 1-800-FOR-MERCedes for current pricing and ordering information on the accompanying CDs and DVDs that are available for purchase. Please refer to Service Information S-B-99.00/222J for more on Star Service

Someplace in this site there is free access to the Service Manuals but if your Java Script does not match they don't work.
Links to Startek Manuals
Free Online Factory Repair Manuals - Mercedes-Benz Forum