Mounted it horizontally on the sawhorses to get the shaping started... removed the straps and stood back as the last layer peeled itself off. I had again forgotten to remove a plastic layer before gluing into place! So I removed the thin film and restuck it - Success!
Started to sand it down. This was hard going as the foam is fairly dense. I spun it by hand whilst holding a belt sander to it, steadied by another sawhorse. Seemed to go fine. The rest I finished off by hand with 100 grit sandpaper. It is not perfect, but I am loathe to spend the many hours required for perfection. It is certainly better that the white foam I tried before. I plan to cover it in thin fiberglass and see where that gets me. Most of the minor imperfections I think I can fix at that stage.
