Decided to use 5/8” marine plywood, since there aren’t any gaps in the wood and will hold up to any moisture, especially when I bend the wood. Took the cardboard template that I scored to determine the curve & height and transferred to plywood. Experimenting in making the correct curve, I cut slots in the plywood, hopefully deep enough so when bending, I get a smooth surface. I decided to pre-cut the sides of the lid so I wouldn’t have to try to cut when it’s bent.
Made a makeshift tank and submerged the wood. I used load binders to help bend the wood and ratcheted about every hour a little more to increase the curve, hoping to not split the wood. We’ll see tomorrow how it turned out when I pull it out.