replacing the windows was my project last spring. I took a template of the existing window and had new plexi cut. I went untinted and it looks sweet.
I then smashed out the old windows. I tried using guitar string and a person in side, after pulling back and forth a million times, and breaking the string repeatedly we gave up. I even tried cutting it all back with a sharp knife a few times.
smashing the windows and doing a straight repair is the way to go!
the previous owner had the windows held on by screws. Once the old windows were off i cleaned the mounting surface, removed all the cracked gel-coat, re filled, sanded and sealed the surface.
I used a double sided adhesive strip and 3M 5200 to seal the windows back on.
The boat went through winter and spring storage (outside under a tarp) with out a single drop inside. dry as a bone.