Here's a last look at the inside of one of the amas before top & bottom were glued together:
The upper one above is the top half of the ama. After a straight-sided channel was routed on the underside of the deck, the corner was cut off with a utility knife to make the bevel. Trying to get rid of as much foam as practical. The bottom didn't get routed at all.
Top half is at left above.
. . .
The amas are now single pieces, complete hulls. Here, one has been shaped, the other awaits the sandpaper:
The corners were rounded with coarse sandpaper by hand. A sanding machine at this stage takes off too much material. One needs to go slowly.
I could probably spend a couple more hours on the shaping, as there always seems to be a little hump here or there to smooth out. We'll see how much patience I have for that...