you will be right netwolf,
- do it on the carpet at home,
- undo the 4 or 5 screws on the side at the bottom of the outside of the tube.
- lift the tube up and out of the way.
- there are then three vertical screws that hold the mirror down via a little rubber angle. undo these and put to one side.
- you can then lift the mirror out of the base and onto the carpet, face up!!!
- i centre spotted mine with rulers, but the best i have heard of from this forum is to get a piece of paper that is bigger than the mirror. put it on the a hard surface, say a book on the carpet.
- then place the mirror on it face up and then trace the circle around the mirror.
- remove mirror and then cut out the circle.
- fold circle in half and in half again and again and again.
- unfold and you should have a very accurate indication of what is the centre of the circle.
- place over the mirror and align edges
- with a small marker, press down in the centre of the paper. this sould leave a mark on the mirror underneath.
- Take paper away
- either make spot bigger with marker or place the sticky ring binder around the mark.
I used the marker and made a spot. I do not see the spot at all, unless it is daytime and i am way out of focus.
Good luck
(mike i will try and put pictures to this one and submit as an article) can anyone else please proof read these words and comments for changes?