I made up some patterns from scraps of ply to rough cut them (holding an 8'x4' panel against the hull to mark it off is not all that practical)
They are now clamped to the hull, with a few strategic clamps, and a few truckers hitches pulling the plywood into the required shape. I'll tighten them up each day as the wood takes a set.
I still need to scarf the foreward and aft panels together, but the bend is all well forward of the join, so it should not be a problem.
I can see a completed hull in my near future.