I finally have the 3d-printable design good enough to throw onto thingiverse and here and consider it 'good enough' to fully release.

(Here's the thingiverse link: https://www.thingiverse.com/thing:3796426 )

I've got the files zipped up and uploaded as 'OHI Science Tricorder V6 Chassis - Release ver.7z'

It's pretty easy to assemble, you just need a small handful of hardware besides the internal electronics. Specific parts and notes are in the Readme file.