Given the plans had a 1.6" thick floor. I used 2" which allowed more shaping and a greater curve on the bottom.
I first made a mock nose using the A plans sheets for the size. This way I could match the curve of the nose that will be built later. I spent a couple of days removing 0.4" at each end and blending into a usable curve as shown in pic 2 below.
This was just adjusting the bottom (or top in the photos) using a large sanding stick. The idea was to get these angles as correct as I could before beginning to shape the sides.