I don't think the dial on the bottom panel actually goes to this dishwasher.
This is what I think happened. The dial and front panels belonged to an earlier dishwasher that was replaced. The panels match the cabinets, and were a popular style in the early 60's, so this machine is probably a replacement for a 14 or 15 series. They likely wanted to use the matching panels on the new machine, and didn't want a hole showing, so kept the dial knob attached.