I just replaced the passenger side motorized mirror in my wife's Saturn, and its motor was inside of the actual mirror casing. I think that this idea will work, but I am not sure about changing the mirror switch to also control the camera. I am sure that it would be possible, just not by me.
A simpler idea might be to re-work the camera pocket to get it set at an angle that will suit all of your needs. The moving camera sounds very cool, but it also will be a huge undertaking to get it usable.