Inspecting mine, it looks to me like you pry out a cover on the front side of the mount that the visor clips into; I'm guessing there's a screw under it.
On the swivel side, it would appear that you have to get a panel removal tool under the circular trim piece to pop it off; I'm guessing there are screws underneath it.
On the swivel side, it would appear that you have to get a panel removal tool under the circular trim piece to pop it off; I'm guessing there are screws underneath it.

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