Some of the vacuum motors can be accessed right where they are, some you remove a bit of trim to gain enough room to change them out. Now for the really bad part, a few of the fresh/face vent motors can only be changed out with the removal of the entire dashboard. I've seen people try to sneak them out and not remove the dashboard, but it can get ugly if things go wrong. Take your time, and try this site for more info,www.homestead.com/BMW_7_Series/Files/index.html. All the HVAC info should be here for the most part regarding a E-23