Looks like a great set up. I've just purchased the same shelf and I was wondering what length RAM arm you installed. Now that you've installed it, would you use the same one again or a different size?
I used the ram arm that came with the 660. It measures about 2.5" total length. It works fine for the stock w/s, madstad, 660 setup, I wouldn't change it.
I've got a different setup I'm working on though, and it's not quite plug and play. I've got a Pat Walsh Designs shelf that I want to mount. My plan is to put Martel temp and voltage meters on the underside of that shelf. I don't consider it strong enough for the 660 though, and want to continue to use the Richland Rick mount. Unfortunately things don't fit out of the box. The ball, mounted facing to the rear, conflicts with the shelf. Mounting the ball to the front conflicts with the windshield.
I'm considering a couple of options. First, I have a Cee Bailey shield on the way. It may have a shape that allows the ball to be mounted forward. I suspect I could add some spaces to move the windshield out but worry about vibration and reliability. Finally, I could use some sort of ball mount that moves the ball up and back. Perhaps I could even use the handlebar bar mount that comes with the Zumo, and just bolt it to the Richland Rick mount.
Another option is to leave the GPS as it is, forget about the Pat Walsh shelf, and just mount the Martel meters on the meter panel. That was my original plan, I just think the would look better on the bottom of the Pat Walsh shelf.
Once I figure something out I'll post a thread.