If they are still glued in solid, just cut them off flush with the covering and install new ones in between the existing hinges. Dont take the chance of screwing up the control surface by drilling out the old ones.

Do you have any idea what cuased this? Are the hinges undersized for the plane? Have you flown this plane so much that they have just become sloppy. Just curious, Inever thought that you could actually wear these things out.