My driver side mirror has been vibrating. One of the three screws holding the assembly has sheered off. Any suggestions on how to remove it?

The house is plastic, so drilling it out might be a delicate task. If the hole is enlarged, a wider diameter screw could be used.

Deven

 

I have never had my covers off so I am unsure what is behind there. If you pop the front cover (white) off, can you see the back of the screw at all? If so, I would get some vice grips on the end and turn it until it comes out. If not, I would try to see what two pieces the screw was holding together and see if they will come apart (removing more screws etc) to see if I could expose enough of the remaining screw to get ahold of. Since it is in plastic, drilling would be my last resort.