here is a summary:
H-34 Fixed Ports Rebuilt | Sailboat Owners Forums
A local plastics shop custom cut the cast plexiglass to my measurements.. Since you are doing only the one, it is short enough to get an online shop to cut it .. I used Tap Plastics in Calif. when I did my hatch lenses.
A couple of things to note: there is no movement of the plexi once it touches the 3M VHB so ya need a way to position it precisely . I used little blocks hot glued to the cabin side, then removed them after the plexi was in place. I used 1/4" tinted cast acrylic (Plexiglas).
The 1" wide VHB is the one to use, and the plexi and the super cleaned cabin sides need to be primed with the VHB primer.
I used Dow 795 to seal the edges of the plexi after the glass was installed. I used a heavy duty wallpaper seam roller to put pressure on the plexi to ensure a good bond to the VHB.. Not a hard one, but it takes some careful thought and fabrication .