Michel:
Excellent work, it looks really professional. Do you do Honda ST1100's?
A suggestion for you, from the "school of hard knocks" - be very picky about where you run the GPS cable. You want to have enough slack that you can adjust the mount to compensate for sunlight coming directly from the rear in the late afternoon. Also, you don't want to get the wire pinched, I had a problem with this once - see this URL:
StreetPilot Cable Failure. When I installed the second cable, I put a fairly long loop in it (you can see this in the third photo from the top), this turned out to be a much better design than the first install, where I tried to hide the cable. Also keep in mind that you want to be able to easily remove the GPSR with gloves on, to do this it is simplest to first remove the GPSR (with cable attached) from the mount, then remove the cable from the GPSR that you have in your hand. This requires a bit more loose cable than you might first think is required.
As for the 'reading glasses' issue you mention, I actually had to get bifocals made specific for the motorcycle - I wanted the GPS to show up in the near vision area, but the side mirrors to show up in the distant vision area - so I hauled the motorcycle down to the optometrist and had her come out into the parking lot and measure everything up (eyepoint to GPS and eyepoint to tankbag map is different - a bit less distance - than what the optometrists normally assume for reading purposes). I was pretty happy with the result, more info and pictures here:
Bifocals for the Motorcycle. NB this thread reads from the bottom of the page upwards.
PanEuropean