Can't eliminate the antenna mount just yet, so the next best thing is eliminating the antenna and capping it off. I didn't want to leave the mount exposed to the elements, so I attached this plastic cap and used some clear silicone to attach it.
EDIT: NEW IMAGE. I took great care to surround the mount with silicone but not get any inside the antenna screw threads, so it's a very quick mod to undo, should I wish to sell the car at a later date.
I know this is the sort of mod that does little to nothing, but it makes me feel better in the mean time, until I can fully kill the mount.