Dana, It's looking good. You're making great progress.
They had 4' x 8' bendy plywood in various thicknesses at my local hardwood supplier. It comes with the bendy part running either lengthwise or along the width. I plan to skin my roof with two layers of 1/8" luan from the hardwood supplier - it's plenty bendy and much better quality than big box luan. I'll be fiberglassing the roof. Have already fiberglassed the sides. Plan to use a roundover router bit at the edge of the roof. Will run the fiberglass cloth from the roof a couple inches down the sides to help tie the roof and the sides together.