Ender 3 Extending Camera Arm

See update below.

I've been using a camera mount on the bed handle (Thing 3077545) for a few weeks now and, whilst I love the design, I noticed that the handle started to sag - presumably under the weight of the camera.

A second niggle was that the camera was very close to the bed, which is fine for small items, but anything large would go out of frame during the printing.

I had previously looked at the mount devised by one_2_three, because I liked the way it bolted to the frame and didn't rely on the stability of other stuff.

My original plan was to simply adapt my existing camera mount to fit that. But then I thought it would be quite nice to be able to extend the distance from the bed to accommodate those extra tall prints.

I still can't get stl files to import into my ancient Sketchup 8. So remixing stuff is a bit of a pain for me: I had to print a copy of one_2_three's original clamp, along with an extremely flattened version of the mounting arm, just so I had somet