I modified the 5cm shaft and added a tab to mount the arm on the case lid and a slot for the camera ribbon cable.

Lid requires supports.

Included .3mf project file was used to print the pictured model.

M3 x 20mm (min. length) bolts to mount the shafts together and to the lid. I suggest nylock nuts. I used spare hardware I had left from my MINI+ spare hardware, so a couple bolts in the picture are longer than necessary. 

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