Hey Ian,

You can wet and heat the strips in that area and pull them down pretty well with a couple of 2x4 blocks and ratchet straps, which is what I did. Then I heated the area again and let it dry for a day or two before I took the blocks off. The pic below is of my Guillemot "L", which has about the same shape as the Guillemot.

When I built my wife's Guillemot I didn't see that the strips had pulled away from the forms until it was too late. It didn't track very well so I added to the external stem dropping it down about 5/8".(next pic)

Happy Building.

Charles.