I'm wondering if anyone out there has ever been successful in replacing the transistor in the W124 climate control blower regulator. It is a similar part on many of the late 80's and most 90's models, The W140's have a factory part with an updated heat sink. The leads can be swapped, but the part itself is pricey.

The difficulty in accessing the regulator which is buried under the blower motor makes repair something that you would have to have confidence in.

Thanks for your replies