Fin insert

I'm going to use the fusion system from FCS, five of them! So the board will be a quad/thruster. For that, I have cut some piece of balsa blocks and spent quit a long time to adjust them for the board. After gluing them, I have figured out that I should may have been using some thinner one. Let say that I love to sand and I had a lot of love to give on those inserts!!!
After hours and hours of sawing and sanding, everything start to look ok! I am almost ready to close the board with the upper deck!