It's so wierd.......the cushion I have that, I'm guessing, would be used for the top bunk has dent marks and holes so it was used at some point. But, there are no marks on the molded fiberglass that holds the bottom seat (and is the storage area) indicating anything was ever attached to support the upper bunk. 1982 Burro
....double hull. I'm not sure about drilling thru both walls to be able to use washers for support.
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