To clear my bike bag I wanted my Dinotte rear light mounted a few inches off to the left side and it seemed that one could find a bit of tube to fit inside the "barrel" to achieve this.
A quick trip to Home Depot yeilded a connector for drip irrigation tubing that would work. I gave it a few wraps of scotch tape and achieved a nice friction fit. Though the Dinotte rear light mount is rather flexy, the light engine itself is small and light and the setup works perfectly.

Nomo

If you want less flex in the mounted light, just rotate the DiNotte mount 180 degrees so that the flat part of the mount is on the left, not right. This shortens the moment arm (leverage arm) of the mounted light to about half the length, resulting in about half the flex.

If vibration of the mounted light is a problem for you or others, rotating the mount 180 degrees to the other side also changes the natural vibration frequency of the mounted light. Then the natural frequency of the mounted light may no longer match some frequency your seat post vibrates at.

Nice mount, by the way.

Huh, I guess some of us just weren't cut from "engineer" cloth.

Nice suggestion, and I'll make the switch for sake of best practice. But vibration isn't a problem as currently mounted.

Mike