I think you'd be better off just buying a new motor, which isn't too expensive, and swapping over your original fan blades onto it. If you're going to go through the trouble of getting to the blower motor, you'll probably want to put in new components so you don't have to go back. I'd consider a new resistor as well.

I can't find it now, but I remember a guy on the 190 revolution board taking pictures of the process of replacing his. From what I can recall, the pictures and write-up were quite detailed. Maybe you'll have better luck searching for the thread than I had.

I wish you luck.

-Mike

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1989 300CE - 269,000 km
1994 SL600 - 59,000 km