I've got a Waltham Riverside movement, #4869178, 16s that has a stud sticking out the side. I went to put it in an open face case and it will go in except where that stud is. Just won't sit flat. it's not a dial face retaining screw. I looked at it thru a Loupe and it is just a stud sticking out of the case. I'm posting a pic of it. No idea why it's there or what it's purpose is. Any ideas?
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