It worked for me with Apple’s 8TB Mac Pro Upgrade Kit. It worked fine but I had to choose restore, not revive in the Apple Configurator and it eventually booted to a folder with a flashing question mark, it did take awhile so be patient. Then I just booted with Command + R and installed a fresh install of Big Sur. Now I have a iMac pro with 8TB’s of internal storage! It’s a bit old but still worthwhile! Plus it’s using an Apple part so I feel good about that.