Working on an enclosure for a project, I needed to model the gen 3 hardware in order to get everything in the right place. In case it is useful for anyone, I have published it on Thingiverse. Available as an OpenSCAD file or a STL for use in other applications. Feel free to use, copy, edit etc.
You could even print one if you wanted a cheaper but less functional Argon!
When making enclosures, I always find it easier to knock up a model of my hardware, build the enclosure around it, then remove the hardware. Especially if you need cut outs for screens, buttons etc.