They are mounted exactly the same. It is just a spring-loaded fitting that goes into a steel frame, which is screwed onto the chassis.
This spring loaded fitting is used by mercedes since a long time and in almost all (if not all) models.
apprentice, I don't know whether your car has the remote (un)locking system with the receiver in the rear view mirror...if you do have that feature, you need to search for an auto dimming mirror with the included receiver housing...
with a minor 600+k