I will take some more photos and post them here and somewhere they can be high resolution.
My master clock has no indicator dial. The slave clock I have was mounted on the wall beside the master clock and connected in series with the master via 2 terminals that normally have a wire link. The door has a wooden frame at the top where one could be fitted but the glass is sprayed black. I've seen several photos of this type of clock and all of those are fitted with some sort of dial. It looks rather cool without one.