Hey, thanks for the reply. Just to close this out...

Unfortunately, my chasis number is before the cutoff. My options are change the blower too, or modify one from an S class (as you said).

From looking at the part numbers available on Fastlane, it looks like the part number changed after 1999. I was hoping to do this on the cheap by installing a used one from a mid-2000s vehicle. But I would be hesitant to install a used one that is 11 years old, even if it's the better design.

I don't know where I the idea that one from a mid-2000s M class would work (senility maybe?). It seems that almost all my original assumptions were wrong.