...and this is the fixing mechanism of the S-Type ext. mirror (2004). While the mirror look the same from outside, the fixing mechanisms differs, which make them non-interchangeable. Maybe, if you apply some drastic measures, it would be possible to interchange them, but I would not want to try that. I also cannot se a way to re-use the "base" with fixing points and attach it to the mirror of the other model. Sadly. (I took the picture above from the internet).