You could use some luan door skin. It can take a cuve quite well as long as there is a good structure behind it to shape it to. I was thinking thin corregauted posterboard as well. Its easy to work with and is cheap. Dont forget the shipping containers that was avail on here to place on the deck!! If you need some i have the files!!

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"If it doesnt have a fire coming out the ass end, it isnt worth flying"