The you very much for showing that the T318 is a viable heatsink for AM4 depending on the board. I have gotten it to mount on my ASUS B450-I Gaming using the following (ignore the M4 hardware and fan):
Four M3x20 machine screws
Eight M3 nuts
Dozens of washers
The backplate from a Noctua...
The G-Atlantic GA620 and GA630 may be similar to what you're looking to achieve. You can get it without an ODD cage and with a PCIe x16 riser and a dual slot and dual PCI slot cutouts. Information on the case is here: http://www.g-alantic.com.tw/1088/ga630/
It would take some modification to...