Just a note that he continued on his path of innovation w/ Ken Parker Archtops, which he was still involved in building until just before the end. These are $20k+ custom orders so there aren't too many in the wild.
Wow, so you can adjust action with just a screw at the back? I wish it were that easy on nylon-string guitars instead of having to file and shape nuts and saddles. The last time I made a saddle from a bone blank I spent hours only to find I'd messed the curvature up.
The neck 'join' in particular is wicked: https://kenparkerarchtops.com/guitars2