I had to make a template of the bulkhead and where the hull was so I could figure out how to repair this. As you can see above I was making a cardboard template to see if I could replace the whole bulkhead in one shot. As it worked out I found out that I would not be able to use one piece of wood. Soooo, I sat back and looked again. I could just make a piece that would replace just the rotten wood. Below is the first template I made to just replace the rotten wood.
(Man, did I itch after that. I was wearing shorts and the fiberglass is not painted where I was sitting!)
Below is the piece I cut out of 1/2" plywood. The original wood was 1/2".
I fiberglassed in the piece with 4" wide cloth at all the edges inside and out. I also fiberglassed it to the deck above, it was not installed that way. I figured it would only help.
I will also fiberglass it to the new v-berth front piece of wood (The bed floor). Look at the pictures above. You can see where the wood has pulled away from the hull. The piece was cut too narrow and the fiberglassing on the wood was not that well. I have removed that piece and have a new wider piece ready to be installed.