Sunmil BG3 is
Already supported
Brackets are on tracks = can move it along the bottom or front.
Any chance you are still considering making a mount to put the PSU in the front of the case so short PCIe cards could be used in the lower slots like was discussed on the original CX2 design?
Below is a picture to give you an idea of what I am saying. There would definitely need to be some thought on which way to face the PSU for cable routing, but I think it might be worthwhile.
Already supported
Brackets are on tracks = can move it along the bottom or front.