Depending on the thickness of the fiberglass original.2.) balsa has to be replaced with PVC foam sheet 2 layers 20 mm and put fiber BX 400 g The bottom 1 layer. 1 layer and between 1 foam layer.
Depending on the thickness of the fiber 2.) balsa has to be replaced with PVC foam sheet 2 layers 20 mm and put fiber BX 400 g The bottom 1 layer. 1 layer and between 1 foam layer.