Best place to purchase one is a junkyard. The part new is over $100.
It is located on top of the blower box, directly below the center of the maxifuse center.
To change one out.
Disconnect negative battery cable. 8mm
Remove strut tower brace. 4 13mm nuts on struts
Remove Maxifuse center from firewall and lay on motor/pull forward to gain access. 2 10mm nuts (one on the left is easy to find outside the box, the right one is inside the fuse center to the right of the rightmost relay.)
Looking at the top of the blower housing, you'll see the electrical connectors for the BCM. Dixconnect both of them.
Remove 3-4 screws holding the BCM to the box. I can't recall if they are 5.5mm or 7mm.
Put new one in and reassemble. BTW it'* a good idea to clean any debris in the blower bos at this time.
00 Regal GS: All kinds of cool stuff.