I learn something new everyday on my W111. I didn't ever notice, but yes, there are sheet screws holding the top front part of the door seal to the door. See attached. Looks to be (5) screws per side and all just below the vent window. Second attached is the screw. It is a 3.9mm x 13mm Pan Head Phillips drive in yellow zinc.
BTW, coming soon are parts for W111 two cars and others - the roller kit for the rear qtr. is done (Authentic, Millers and Bud's Benz) and the rubber drive coupling for early power windows is almost complete. The final part is a way to rebuild the early type power window switches. I'll post something on this when it gets closer.