We're using the wonderful snap-fit case designed by the Ruiz Brothers for the Circuit Playground Gizmo Ornaments guide. We'll modify the case just a little bit after printing to make it fit our project perfectly.
TFT Gizmo Ornament Parts
These parts are designed to house the TFT Gizmo and Circuit Playground Bluefruit. The parts snap fit together and secure the PCBs in place without the need of glue or screws.
I found that the top and bottom pieces printed fine with no supports, but the cover needed support turned on, in order to print correctly.
After printing, the one modification we'll make is to use flush-mount cutters to remove the supports at 11:00 and 5:00 on gizor-tft-bottom. These two supports don't fit if we put screws in all 12 screw-holes (the ornament project only required 10 screws and these two spaces were left empty). Other than that, this case fits perfectly!
I used temperature-sensitive filament as well, so my necklace changes from a light blue when it's cool to white when it's warm.