Updating MP with an rx 580

Hi all,

I recently flashed my 4,1 to a 5,1 and installed High Sierra to get my RX 580 working properly. One small issue is that I don't know where to go from here, considering the 580 isn't a flashable card.

My question is, how can I patch MacOS 13+ (preferably) without a bootscreen? Can I do the process with the OG GT 120 installed at the same time?