After mounting the window the fiberglass is wrapped around the "nose" of the Class C rv.
All of this wood was completely rotted. So a little thought and a lot of "cut to fit" was used to allow the fiberglass to curve around the nose. Cypress was used to help prevent rot in the event of a leak.Be sure to use an odd number of profile curves. You want to have one in the center. When you start to bend the fiberglass, start in the center and work outwards a little at a time to each side. If you start on a side you can end of with a small twist or diagonal to the fiberglass and the opposite side is not going to match up correctly.
Once again a layer of black butyl putty tape is used where the fiberglass seams join.