I powered off, removed the door from the unit, removed the aluminum cladding from the frame and then removed the UI unit. I had to work a little to pry the UI unit open without damaging the case. I set the 'personality jumpers' based on the included instructions per my model number. Then it was pretty trivial to re-assemble the UI (buttons + control board + case) and then put the whole thing back together. The applianceblog was clutch!
https://www.applianceblog.com/mainforums/threads/ge-dishwasher-gdt545psj2ss-intermittent-loss-of-power-to-the-door-controls.94622/