Here are some more fotos that may help you.

The fan clutch is attached to this assembly



There is a notch in the side see next foto



You need to make your self a tool from quarter inch rod and bend it slightly at the end. You need to insert it into the notch and in one of the holes in the pulley as shown


Once this tool is in place you then start to remove the fan clutch with the allen key and assembly (anticlockwise.)



You can see that this is a w124 260e. There is a suitable amount of room between the radiator and the fan clutch. However if the bolts are frozen on you may have no alternative than to remove the radiator. This is not
a difficult job either. If you remove it make sure you give it a good fluch out.