Would seem to me that adding an icon to gunners wouldn't really work.  Imagine trying to take off from a CV/fleet with a lot of gunner's icons cluttering up the screen.  What I would think could work would be to add the name to the screen in the hangar when you're selecting to your plane/gv/gun position.  Or number the gun positions and provide a ledger with who's where by number. 
Then again it could just start witch-hunts.