I think you should prebend it. On the Spring Run, the procedure is to glass the outside of the deck, then remove it from the forms, tape off the forms and the hull, and sand and glass the inside. When the inside glass is still green, attach the deck to the forms and let it cure.

I havent tried bending flat panels, but I suspect that the only way it might work would be to glass one side, then bend it and then glass the other side. If you try to glass the outside first, holding it in shape while glassing the inside will be a PITA. If you do the inside first, then bending it around will open cracks on the outside. But perhaps, with plywood, and not much curve, it would work. I'd suggest treating the ply like strip.

: The rear deck of my plywood walrus will have a slight camber to it. I will be
: glassing the inside prior to installing it and am wondering if I need to
: try to prebend the panel or will it be ok to glass it flat and then form
: it to the deckbeams???