I will post again when I receive the Fenvi HB-1200 card and modify a full profile bracket to fit the Fenvi card to allow for using the proper slot space but offsetting it from the motherboard so the riser connector has room to fit onto the HB-1200 without interfering with the white PCI connector.
As promised, I am posting to show the result of my mod of the HB-1200.
Below is the Fenvi HB-1200, stripped of the original bracket. I had an old one lying around that I drilled the appropriate holes in to accomodate the Fenvi. Remember to offset the holes in the bracket so that the card doesn't interfere with the connectors on the motherboard when the whole assembly is inserted.
The Fenvi came with a couple of yellow caps for the SMC connectors - using an X-Acto knife, I carved off a ring of each to use as a washer/spacer for the assembly. Waste not, want not
Next, I fitted the assembly outside the case to see if everything seemed solid and in place. A word of warning here - the green status diode is a bit fragile and mounted in a housing that is soldered to the PCB. Be careful to align this with the hole or it will be pushed away from the bracket and might get damaged. Since the whole thing is held together by the antennas when you fasten them on the SMC connectors and tighten everything together, this is worth paying attention to. And you
will have to seat the bracket without card first and then align the card and finally add and tighten the antennas last. It's a bit fiddly but is tight once it's done!
From the outside, without antennas (I am supporting the card with my hand inside the case):
It's a tight fit inside the case
(if you have an NVMe adapter in there, I suggest removing it first and re-seating it when you're done)
Final shot from outside, everything assembled
I am really happy with this solution since I don't have to drill holes in the case itself. That would require me to remove everything from the case and thoroughly cleaning it afterwards, to avoid having metal shavings finding their way into small nooks and crannies.
I have tested in Windows 10 (the install that the 9020 came with anyway) that everything works - the riser cable is perfect length, and I am happy that it is extra shielded compared to the budget versions out there.
So come weekend, I will remove the Windows SSD and start installing MacOS Catalina - yay!