I had a Kuryakin fuel door mount for a long time before I modified a ram ball mount by cutting off the ball and mounting the round flat plate on a bar mount. It sit low on the bar on the left side.
I think T and T fab is on to something. Just what I'm looking for. Appears to be easy on and off, I only use the GPS a few times a year at that time I am putting the taller windshield on for the trip, might as well put that mount on, clean easy, and easy take off when I get home with no unsightly mount left behind.
As requested, to post pics of combination of HD handlebar mount (older version) and supplied Ram mount with Garmin Nuvi 340LM. Had to turn bracket vertical, and used combination of screws and such from both kits.