Fan adapter
thingiverse
The ceiling fan I have is odd. I had to make a special adapter to put light covers I want on it. Assuming this one will work. You just need to go in Fusion 360 and make your attachment with the thread. Cut out the hole using something like 3D builder. Then attach using 3D builder or whatever tool. Now you can just thread whatever light cover you made on there.
Download Model from thingiverse
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