Gigabyte Z87: No ReBar after applying FFS

Setup:

Things I tried:

Above 4G Decode:

Followed the guide to enable hidden 4g decoding by booting grub shell efi from a spare Windows USB:
- EDIT: Just checked the FAQs and realized that Memory Remap is not what I was supposed to be looking for...
- EDIT 2: I'm not able to find the Above 4G Decode offset from the files that IFRExtractor outputs. I do see the following string in the hex view in UEFITool though:
- Above 4G DecodingEnables or Disables 64bit capable Devices to be Decoded in Above 4G Address Space (Only if System Supports 64 bit PCI Decoding).

ReBar:

First thing I tried before I found this repo was applying the registry edits for enabling ReBar on unsupported GPUs, but I now realize that probably doesn't apply to my hardware anyway. I left the registry edits in place as I continued with the next steps.
Added FFS module to F6 BIOS from above hardware section
Flashed BIOS with patched version
CSM off
Secure Boot off
Played around with TOLUD (not sure if necessary or applicable, left it at 0xC for 3.25 setting for now, default was dynamic or 0x0):

xCuri0 / ReBarUEFI