Thumb rest for sony A7C

I recently upgraded my camera from Sony A7M2 to Sony A7C. As much as I love small form factor cameras, the ergonomic of A7C is not ideal for my hands. I have seem people using thumb rest for Leica & Fuji cameras and I have always though it to be a great idea. So I decided to design my own thumb rest for my A7C.

The thumb rest is mounted on the hotshoe. The initial geometry of the hotshoe cover is taken from Sony hotshoe cover by Anatoly S from GrabCAD (Link: https://grabcad.com/library/sony-hotshoe-cover-1). I planned to modify on the original STEP file. However with increasing amount of tuning and fitting, I decided to create my own CAD from scratch. So the geometry is a bit different from his/her original design.

Suggested to print with 100% infill and material more durable such as PETG. The fit should be a tiny bit tight so it will not wiggle too much when you apply force with your thumb. On the other hand, I am not very comfortable with a really tight fit, since I am not sure