Not true. 47-55.1 use the same arm. See attached screenshot from the parts manual (if it works.)
I don't question what your attachment might indicate (even though I can't view it due to the current glitch in the Stovebolt Matrix), but I beg to differ. I have a bone stock '52 mirror bracket and it is clearly different than the '50 and earlier arms. The '52 mirror sits much lower than the earlier models in order to clear the open vents windows when you open the door.
