Carefully shaped two divinycell pieces to fit into the area bounded by the lower wooden longerons and back seat support. This took a couple of hours but made a very tight fit.

After gluing in place with wet micro I used very heavy weights to ensure no air gaps and this did produce some excess squeezed out the tight sides.

It will be a good base for the next step.

Shaped foam

Nice tight fit

Ensure all the air is out