Installed the fin boxes today. With the wooden boards, when I need a thicker version of the resin, I take sawdust and mix it in with the resin until it is thick. Then I use that to "glue" things in. This is what I did today - I mixed up a bit of resin and mixed pretty thoroughly with saw dust and put it in the bottom of all the fin boxes and also painted it along the sides.
Here are the fin boxes epoxied in:
Next step is to sand down the fin boxes until they are flush with the bottom.
After that, I am going to clean up the garage and lay down some tarps and laminate the fiberglass to the board. I am also looking for a solution to the vent screw - I have a gor-tex leash plug, but I think that is going to be inadequate. The more I think about it, the more I want to do something like this: