I took a couple designs and combined/refined them. I loved the design of the original adapter, but I didn't want to rely on an actual PopSocket for the back as the are a little unstable. I adjusted the tolerances of the middle adapter to allow for some give. Same for the PopSocket portion, it fits pretty tight into the PopSocket mount so it won't move around as much.

Uses an M4x6MM flat head screw and M4xH6 heat insert to hold all the pieces together. Glue can be used also for a little more stability.

Enjoy!