Windshield Fastening Question

As I was motoring back today to the harbor I noticed the left section windshield, underneath the hinge for the middle window section, has broken its fastening screw. The support strut is still in place but the windshield bounces as the boat moves. It moves around a quarter inch. It looks like you could put a screw into the aluminum frame into it from the inside of the cabin. I'm not sure what I would be screwing into though.

Any suggestions????