I made a tool to remove the radiator fan on my 1987 300E as I did not have the proper Mercedes Benz tool.

Rummaged around in my junk box and found a thick walled metal tube the size of a fat pencil about a foot long that the throttle cable runs through the fan housing on an old VW Beetle. Spent the afternoon filing down the outside of one end until it just fit in the hole in the shaft at the1:00 position mentioned by Karl and Tiger. You will need a flashlight to locate the hole back there. Many test fits including bending an angle in the foot long tube to duplicate the Mercedes tool and allow it to thread down around things to engage the hole.

Probably not worth the effort to save ordering the MB tool, but I am Scottish . . .

Pete Cowper, 2006