Hi there,
and Welcome here…
Actually there is a CAD file? it’s the “stp” file opens in FreeCad and allows easy dimensioning and supports printing a Panel on the 3d printer or CNC with the export. I’m shocked if you do this kind of work, you didn’t know?
just messing with you… 
LOL, maybe you just missed it. I know what you mean about a good old fashion drawing would be nice , but the Stp file is nicer.https://files.seeedstudio.com/wiki/reTerminalDM/reTerminal-DM-Structural-Design-File.stp
here is two pic of it.
Dimension line…
edge to edge measured back look.
front, topish…
HTH
GL 
PJ
