Today I drilled the square keyway holes for the keys to fit in, roughed in a wheel or 2 some more, and I have a nice pair of cedar blanks gluing up for the top. Progress!
With the loose parts all to hand, I can play around with how things have got to fit together, and from there I can figure out how the top bracing needs to be designed to support everything and still allow the top to resonate.
I’ll try and figure out the ultimate siz of the key box and begin assembling it. That will really drive a lot of other design decisions.