I finished putting this together yesterday. I wanted to have a one-piece (of sorts) controller with power supply, so I made these piggyback brackets. the fit turned out perfect, with a nice friction fit between the delrin brackets and the power supply & Blackbox. The finishing touch was the power supply kit that nicely covers & contains the business end of the power supply. I've attached the DXF file here in case anyone wants it.
I did a modification to the piggyback bracket design. Previously, the brackets needed to be slid onto the Blackbox from each side. I had about enough of that after several times of taking it apart and putting it back together, and decided to design in clearance cuts for the screws & switch. Now I can easily slide the Blackbox fully into place without taking everything apart as before. DXF file attached, for anyone interested.