Yesterday, I requested this information again, and this is what I got from Engineering.
Unfortunately, we do not have the stand alone bottom plates for these units.
We suggest you looking into the variety of 3rd party chassis available since many of them have a little more room or can be customized the way a normal desktop case could be.
Remember that if you put or make any additional holes in the Intel unit, even with a replacement plate, it would change how the unit cools and it would no longer be working as designed, which would void the warranty.
Regards,