Love the rugged box model and decided to adapt it for use with my RG35xx I left about 2mm of space all around the device to be able to add some foam padding. For the padding on the face I used the foam that the device was shipped with. The screws are M3 25mm and you will need 6. There is an optional TPU seal, beware this will not make it water tight.
The author remixed this model.
edited the rugged box to fit the correct size used the dimensions of the RG35xx case for the mold of the device.