This post shows how I originally mounted my Zumo. Its a left hand clutch bracket mount using the standard Zumo hardware but I had to modify the RAM piece by grinding / filing. To mount it on the right side, its easiest just to cut that plastic sleeve off with a utility knife or an exacto knife. Its easy to cut.
If you are powering the Zumo off the battery, it would be easiest to just have both connections come off the battery instead of looking for a good frame ground. I would use two
crimp on connectors. Either the ring terminal or the spade terminal style. One that fits under the positive battery terminal bolt and another that fits either under the negative terminal bolt or fits under some other screw that provides a good ground.