According to ETM three stage setup with low, medium, and high speeds was used only on 92 models. It had 2 relays K9 and K9/1 (K9 is actually a module with two relays inside), and two resistore R15 and R15/1. As of 1993 and up to mid 1995 MB used only two speeds. Only one double relay K9 was used, no K9/1. From mid 95 electronic module with infinite speed control was installed, no relays and resistors.
You can connect two new resistors in series configuration and use it as with you original setup with two speeds - equivalent to low and high in 92 setup. It is also posible to wire for medium and high if you put wire from the relay to the middle point of two resistors.