I'd imagine the display is still there - but you just can't see it
The bulb is on the back of the dashboard binnacle, which has to come out, unfortunately. The display hasn't started to show a crazy mileage, by any chance?
John
Typically the plastic shrouds which surround the binnacle have to come off, and the fixing screws for the dash become visible once they are out of the way.
Easier said than done without cracking the plastics! I'll confess I haven't taken the Extra dash apart but I have done a similar vehicle - I think it was a Citroen Dispatch. At least there's no speedo cable to unclip these days, so there's enough slack in the cable to unplug them!
Maybe you'll get some clues from Youtube or whatever, and good luck with it if you decide to crack on!
John