Exactly. Like when I took the maximum thickness of what is now my vertical rudder (previous owner's hand made daggerboard) and made a foil template out of cardboard (NACA 0012 airfoil) where the maximum width of the foil was the thickness of the old, flat daggerbord, in order for everything to work out and match the NACA 0012, the chord of my rudder was only going to be something like 8 inches wide.The issue I see with making a good foil is that the curve has to be fairly mild overall, as the daggerboard isn't all that thick to begin with.
That's correct.Your total length must be TOTAL length (from the very top above the stops)