I'm betting you have to remove the ashtry, move up the monitor, and then re-insert the ashtry to hold the monitor.
I thought about this, but ended up going with a window camera mount that has two gimbals, and a clamp plus the pad that attaches the monitor like a camera.
The reason I did not go with the ashtray is you can't adjust the screen to the perfect angle. Also it's too low in the dash for easy reading.
It is a nice way to hide the Profec however. With mine, I just loosen a gimbal, and drop the screen down so it's not easy to see it. (Also nice at night when it's too bright even on the lower setting. This has only been a problem in very dark areas, like between Elko and Ely, NV where there is NOTHING.)