The Rhodium is a modification of a Polaroid 360 to take 4x5 film. The Zeiss Ikon rangefinder was reversed engineered and a corrected cam was 3D printed to match the new adapted lens.
The files can be downloaded here. the body was designed to fit the 360, and attaches with two couple of very long M3x35 screws as well as two M1.6x10 screws. It is designed for the 135 f/5.6 Caltar-II N (Rodenstock) For any other lens you’ll have to modify the piece to adjust backfocus.
Graphmatic backs can also be used