1950 Mercury rear fender removal

[drgoetz]

My 1950 4 door Mercury needs the rear fender rust spots repaired; in the usual spot, at the front of the fender. (I can not find patch panels.)
How do these fenders come off the car? I can see where they are bolted, however, how are they removed just behind the rear door ... soldered on? I have checked the parts books but do not have a clue at this connection. I can not find a seam.
I want to hang my fender skirts but am really afraid they will both "fly off."