Welcome to the club, I have the same car.
My suggestion, based on recent experience, lift up all the floor mats. You'll find this plastic coating. start poking around at that with something sharp and look for rust. You'll feel soft or crunchy spots. It hides in there and will come back to haunt you later if you don't take care of it now (better to catch it early). These cars are notorious for floor pan rust, especially in the rear pans. See my recent post:
http://www.peachparts.com/shopforum/showthread.php?t=218803
Other than that, I'd suggest running processed biodiesel as opposed to SVO. SVO gums stuff up, B99/100 burns better and is better for the engine. Find a good local mechanic that specializes in diesel benz's, every town seems to have them. One that you can develop a relationship with. Have him go through and give you a list of recommendations, starting with "must do" and finishing with "future recommendations".
Good luck, and welcome to the forum. You'll find lots of useful information in here and many people eager to help (and a few eager to make you feel like an ignorant newbie, don't worry about them!).