Ender 3 Pro MeanWell PSU fits perfectly under Y axis extrusion in the back.
You can print 1 or 2 front parts (to be put into cenral 4040 extrusion), I decided that one is enough for me.
To fix left and right part you will need 4pcs M5 screws (I used ISO7380 M5x10) and 2pcs M4x6 (I used ISO7380 M4x6)
There are 2 versions of the left parts with different power plug fixing screw holes diameter.

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I started do design a mount to attach the power supply to the bottom front. Many of us use a rear mounted case for the electronics, therefore the power supply have to go to the front.
This project is work in progress. I just uploaded it, that others can help to improve this thing. I already printed a first prototype and it is usable but nowhere near a finished design.
Please keep in mind that you have to increase the length of the original high voltage cables. Do it at your own risk!
Things to come:
In the end the PSU should be totally covered in a housing for a better look.