I've done this job twice now on my '90 300CE and I can tell you that you do not have to remove the radiator. You do have to remove the fan, but you can avoid messing with the "special" tool by just removing the plastic fan blades from the fan clutch. You will need some hex sockets for the job (5 and 10mm I think), and long wrenches, especially a gear wrench set, help a lot. Give yourself some time to do this the first time around. It will take some time to figure out where all the bolts are, and how to remove everything.

GregS
'84 300D, 183k
'90 300CE, 173k