I took iPhone 12 case from https://www.thingiverse.com/thing:4651702 and added the Rileylink case portion from https://www.thingiverse.com/thing:4661374 to create this case. I prefer a deeper bumper around the screen, so I added that to this case, plus a matching bumper ring around the camera lenses. There are two holes in the Rileylink portion of the case to add LED light pipes. If you have transparent PLA filament, just shove a piece of that filament into each hole until it touches the RileyLink, then trim off the excess. This way you can see the green (connected) LED and the red (charging) LED if you print the case with non-transparent TPU filament.

The original iPhone 12 case needed a small size reduction to fit the phone tightly, and that reduction has already been made on this model.

I filled in the Rileylink case hole for the on/off switch. I seem to always break my Rileylink on/off switches when trying to reach them with a paperclip through a case. So I just take the phone and Rileylink out of this case in the event I need to power cycle the Rileylink.