Articulating mount for Ecobee Room Sensor

I'm using Ecobee room sensors (the older style) as motion detectors and wanted to be able to adjust where they point. I have designed the mount to articulate in 2 dimensions, which combined with the way the sensor rotates around the cover gives the full 3 degrees of freedom.

Notes:
1. The wall mount has the same mounting hole as the original wall mount, so you should be able to reuse the OEM screw. I'm mounting them with a double-sided tape though.
2. Wall mount can be used directly with the sensor cover (that is, without the arm). This looses one degree of freedom, but makes for a more compact installation.
3. There are two variants of the arm - a short and a long. The short one should be sufficient for most installations, but the sensor would bump into the mount when turned close to 90 degrees. The long arm adds 5mm and allows the full 90 degrees and can act as a table stand (although it might be a bit unstable if used without a tape).

Printing and assembly:
- Wall mount pr