Hello,
in contrast to the 250-280SL but same procedure, the 230SL does not have a viscous coupling, but a fixed radiator fan that is attached to the water pump with 3 screws (4 for 250-280SL). For assembly, it is helpful to remove the hood (otherwise it is a nuisance or you do it from underneath), protect the radiator with a cardboard and release the fan belt at the alternator. Otherwise you can simply remove the 3 screws and mount the new fan.
...WRe