Does anyone know how to fully strip the side mirrors down fully? I’m painting all the visible plastics and metal mounts but I’ve hit a wall.

I’ve removed the mirrors form the car. Removed the class, the painted covers and black plastic trim that surrounds the glass.

I can’t get the remaining black plastic trim free from where the swivel point is. It appears there are 2 grub screws holding them in place but there’s no way of getting a screwdriver to them. Any help would be much appreciated.
Thanks