By applying the bent ribs on the corner blocks, it was clear that the cuts were inaccurate. So it had to be a start over.
It’s a relief that I didn’t use the actual spruce tonewood but some scrap wood. I took another piece of white wood that I got from a home center. Even without glued on the mold, I practiced cutting it with a gouge.
The problem was that the curve was not perpendicular to the flat ground. From the information that I saw, it could have been possible to cut this almost only by gouges. That amazed me but as I did this a few times, I was getting to feel it wouldn’t be completely impossible.
I think a few more practice with scrap wood should be done.