Best way to upgrade a 10.13.6 nVidia hackintosh to Catalina and RX 5700 XT?

Hello hackintoshers,

I've been successfully running this hackintosh for about two years now. I already have a Gigabyte RX 5700 XT here but am a bit shy with diving into the upgrade, trying to do as much research as possible before I dive into it. First thing I did before I even bought the card was prepare a backup of the working system, both the EFI folder and a carbo copy clone on an external drive. I also have Time Machine backup.

My current system is:

• MSI Z170a gaming M5 (yes i know, now, did not know when I bought it, that's why I am researching better this time, not the best choice for hackintosh)
• Intel i7 6700K
• MSI GTX 970
• Dual boot with Win10, both on Samsung nVME drives.

I am going to upgrade the GPU with the Gigabyte RX 5700 XT and also the SSD to a Samsung 970 Plus 1TB, so I will not have to touch the original working SSD and can always fall back to the kown good configuration in case something goes wrong.

So now the question is what's the best way to go for the upgrade?

• ditch the safe path, and just run the usual software updgrade with the nVidia GPU and then just change GPU and migrate to the new SSD later? (least favorite path)
• do a fresh install with the new GPU and start a fresh system from scratch?
• do a fresh install with the new GPU and recover the configuration using the time machine backup?
• or would it even make sense to do a fresh install with the old GPU and then switch to the Radeon after install?

My personal tendency is the fresh install using new gpu and time machine recovery.

I have already prepared an installer using the latest installer from the appstore (15.1.03) and configured a config.plist using this guide. So basically all that would be left is swap SSD and GPU and give it a try, but I have the feeling it is better to ask for opinion first.

So the question is, have I overlooked anything? Is there maybe an even better path?