Here's a little more detail. Open the hood. Remove the plastic air plenum (hollow box) that goes across the car just at the base of the windshield. Several philips screws hold it down. You may have to remove one or two vacuum lines on the passenger side. Move the plenum aside. You'll see the filter for the outside air directly below. Simply lift it out. If you haven't changed this in the last year, change it now.
Directly beneath the filter, you'll see the top of the blower and the regulator. If you do a search, you'll find pix of this.
Don't forget to use heat conductive paste between the regulator and the blower.
Hope this helps.

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KenP

1996 S500 W140 Coupe