Look for my thread on my 200. It's about the same procedure.
I have pictures and details about when I replaced my head gasket. As someone said. this is a harder procedure than most activities.
1. First find the C link as someone mentioned. Be careful and not drop the link and clips into the motor. I usually set the engine to TDC, then remove the link. I also mark the distributor and make sure it's TDC by taking the valve cover off and making sure the #1 valves are closed. To prevent something falling into the engine, I stuff rags around the area, so if the link falls, it just lands on the rags.
2. Get some wire, and do not let the chain drop into the engine. This should not be much a problem if it does, but its a hassle.
3. Then you can start to take the engine apart. You will need to remove the chain guides. (Again, best look at my thread about it.)
4. Much more disassemble and best to look at the manual. This should get you started and then you can ask more questions.
5. Inspect the motor. If the coolant has not been replaced at regular intervals, there could be damage to the motor.
6. Before you spend money on the head, I would have it pressure checked. No sense spending money on a bad head.
Usual caveats. I am not a professional mechanic, and these comments are my opinion. USe are your own risk.
Hope this is of some help. I got lots of good help, as I was doing mine.
Link to my thread: http://www.benzworld.org/forums/vint...966-200-a.html