I want to know the same thing.

On my W203 C240 the front portion of the engine cover snaps off, this is the portion that surrounds the oil filter, it is about twelve or so inches deep.
Starting on the driver side push up and work your way to the passenger side.

I did notice that the twin air intakes over the radiator are connected to the housing that covers the intake runners, but I could not figure how this piece is removed.
I may try www.startekinfo.com