The famous "breadbox" dome light shared among 1960's Vintage MB's....... half-way open means car doors will light it up - full open and its manually illuminated. You need small thin flathead screwdriver to remove it. Probe for indent on right side, it oughta push to the left and then pry out downward.

This is state-of-art Vintage MB component built with surgical precision, shares bulb with rear dome light. You can scuff the contacts with sandpaper, it oughta help. And bend contacts tighter with extreme precision if you dare.