Wanted to do a quick post - I found a90 degree PCIE cable that fits under the RX 580. So I was able to install the Fenvi network adapter, and a PCIE to NVME adapter without cutting the case. I did modify the brackets - I have the 1200 series card.
Here is the adapter I bought
https://www.amazon.com/gp/product/B07ZKQNL1S/?tag=tonymacx86com-20
To install was easy - obviously the adapter plugs into the 1x PCIE slot. After that, what I ended up doing was slightly modifying the two brackets that came with the card.
There is a low profile bracket - I straightened out the part the would attach to the PC with a screw and attached it to the card.
I then took the normal card backplate, the full sized one, and ground away the lip on the back side, and cut off the two screw tabs that would mount to the card.
plan is to mount the two together. The low profile bracket servers two purposes here - It spaces out the LED since the hole will not line up, and will server to let me drill some holes later
Next thing was to just mate the two together - my plan is to add some screws to hold them together, but right now the antenna's are holding the card to the backplate in the PC.
Should be more obvious from some pictures.