I have a driven top triple and used the two bolt holes for the ignition to mount a plate. I have GPx mounted on the plate. I don't think I have a photo, I will check...
DCMoney made up a mount for me to mount my GPX. Basically, its just a flat piece of metal bent in to a "square U" shape like this: [
The mount fastens to the the top triple clamp where the ignition lock bolted up on the bottom. There is velcro on the top and front of the mount. The GPX mounts on top and the receiver mounts on the front. These are the best pics I could come up with, for now: