Clavinet D6 Disassembly Guide Page Three
Remove the thumbscrew located are the top of the left wood panel containing the binary switches and volume control.
Since the left wood panel is electrically attached to the keyboard, simply set it behind the wood block standing up.
Locate the two screws on the left side of the keyboard assembly, the lower screw has a "castle-nut" shape. Remove both with a standard screwdriver.