mounted mine to the optional BMW mounting bar and respective clamp. removed the headlight/instrument cluster to facilitate getting to the mounting screws. that part was easy. attached the clamp, then the GPS bracket/housing, but the mounting screws seemed almost too long, so washers to the rescue (will buy shorter screws, proper lock nuts). then i wasn't satisfied with how it sat (a bit low for my liking) so i flipped the mount (as described above) upside down but it didn't seem to fit (would hit the GSA windscreen bar), so back to the original position it went. i like the fact that there is a dedicated mounting bar for it but you'd think for the added pieces and expense that it would be perfect, and i don't think it is. i will say that it does offer a very clean look and puts the GPS just below eye level.
2012 Vespa 300 Super
past: Ducatis, Aprilias, Moto Guzzis, a Husky, KTM 1290 SDR, and some BMWs as well.