How hard is this to do, and are there any special tools required?

In other cars I've done this to it was a simple case of taking it out from the engine bay, but I noticed in the 124 it's under the rear side of the car for some reason

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Smoke Silver 1994 E220 Coupe Automatic
0 kilometers 6 September 1994
100,635 kilometers - 6 September 2010