Hi Jeff, Measurements from a No.1 (no model number so the first #1 model).

I took the measurements twice. Once from the underside of the camera, from the centre of the hole where the screwhead that holds the lens pivot is located to the edge of the wooden film plane. And also inside the camera using calipers from the centre of the lens pivot rod out to the edge of the side wall (holding the film roller). Both sets of measurements corresponded. Hope they are helpful.

If you are making new parts for the Panoram No.1 and make a new shutter release arm, myself and a few others may be interested, as that appears to be one of the commonest parts to stick/wear on these old cameras. Regards Stuart