Many fiberglass boats have a lousy or not well thought out attachement system for bimini tops. Some use the windshield frame which is risky unless it is a very strong stainless frame. What I did with mine was install slider mounts on the inside of the boat, on the coaming panels, which is very strong, and I can slide the top foward or backward out of the way, if needed.
https://www.dropbox.com/s/ao7q5x2adv5z0 ... p.JPG?dl=0you can see it in this pic, if you look closely. This is the strongest way to mount a bimini top in my opinion, wood screws in the coaming panel will never pull out.