2001 Hyundai Elantra, drivers side mirror was.

First thing you need to do is to remove the mirror glass. Check bottom of mirror for any holes that might have a screw. If yes, loosen the screw and pull gently at bottom of mirror to dislodged it and remove. If no scres are found, pry at bottom of mirror and lift. Do not force as you can break the mirror glass. After mirror is removed, you would see screws which has to be removed to get the actuator motor out of casing.