I built this as part of a larger rebuild of my Tevo Tarantula. It is still a work in progress, but I thought I would share this iteration for anyone that might be able to use it.
This mount is designed to allow the power supply to stand vertically with the terminals safely covered. This takes up a smaller footprint around the printer. There is a provision for a power switch/IEC connector (https://www.amazon.com/Inlet-Module-Switch-Socket-IEC320/dp/B00F4MFMXE). There are holes on the bottom to mount it to your base as well as holes on one side to mount to the vertical extrusion of the gantry. There are two 8mm holes for the wiring to exit through, as well as a provision for a 4mm bolt to be used as a strain relief.
UPDATE 2018-11-30: Just in time for the holidays! There is now a base that is vented for your cooling pleasure. This should help anyone that may have a problem with air flow to their power supply. (Thanks styo!)
I have separated the top bracket from it's tab (PS Top Bracket B, and PS Top Bracket B Tab). You can now print them separately and glue or screw them together. This makes anchoring a lot stronger and the part easier to print.
Let me know what other changes you would like to see!
UPDATE 2017-09-03: I have updated the base so that it stands out away from the 2020 by 5mm. This was necessary to allow the Z wheels to pass when going up and down. I have also added the top bracket. This helps secure the PS so it doesn't fall out. It also makes the gantry more stable Win-win!
I sliced it with S3d and used variable processes to change the print height to 1.5mm wherever there were holes or arches. The rest of it was printed at 2.5mm. I used eSun black PLA at 210/55 celsius. I used custom supports for the large window where the IEC connector goes.
The top is printed upright, so there will need to be supports inside. Sorry about that :/
This can be mounted directly to your gantry or screwed down to a table surface. Mount the case, and then run your wires to the power supply. Install the IEC/Switch, and fit the power supply into the top.
Put a 4mm screw into the hole between the cable openings, and then zip tie the wiring to the bolt. This will give you a bit of a strain relief for your cables.
There are currently no mounting holes for the supply (as this is still a work in progress) but mine has fit snuggly into the printed part. I intend to eventually make a top bracket to fix it all into place. For now this should work as is for most people.
The big picture
This is part of a larger rebuild, and I intend to add/edit this model as needed. My rebuild is inspired by the actual Prusa (which the Tevo is nothing like). There will be other parts involved which I will share as I complete them.