Hi Ale 72, I just this week changed mirrors. I bought the one from Heart of England which is a straight replacement for the plastic dipping mirror.
I was advised to be careful about changing it over when the temperature is too cold as the black plastic fitting can snap.
The black plastic fitting is slid down over the windscreen fitting.
So to remove you need to slide the black fitting up (parallel) to the windscreen.
The mirror will move up as well, however do not use the mirror to remove the black plastic fitting.
To install fit the new mirror onto the plastic fitting and slide it down onto the windscreen fitting. As it was so cold mine has got about an eighth of an inch to go to fully fit. I will leave that until the temperature is a bit warmer.
I must say that the Aero Racing fitting looks better than my mirror. I would guess that it fits over the windscreen fitting and is secured via a grub screw.

Last edited by Wirewheel; 24/03/13 08:02 AM.

Ian
2011 Plus 4
Wild Mogs Reims 2019, Goodwood 2018, Isle of Man 2017, Carried on to Caramulo" 2016