I did the one on my 190 last weekend.
It was quite a messy job.
I disconected one of the fuel pump teminals (as I cant seem to access to fuse) and ran the engine until it died (a few seconds).
This releases a bit of pressure in the fuel system.
Make sure you disconnect the battery to avoid sparks.
Some fuel will be lost but not as much as I was expecting.
Its an awkward job and this is what takes the time not the complexity.
I found I had to take all the clamping nuts and bolts out before I could take the old filter out.
I found very little difference to the car once I had done it. But it is a service part that needs doing.