Bird Photo Booth Mount for 2" square post

I purchased a Bird Photo Booth from Bryson Lovett a week ago and needed some way of attaching it to what was once a bird table feeder - I had removed the table part and was left with a post which was roughly 46mm square. (A 2" square planed piece of wood).

In the instructions for his Photo Booth, Bryson recommends using a tripod as a support but I wanted something more permanent in the garden so that the birds could get used to it and I could fit my GoPro camera (or iPhone) as needed.

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