Background: I have a iMac pro with High-Sierra 10.13.6 installed. I've failed to install Mojave several times even when trying from safe mode (and of course Apple has been no help). The symptom has always been the install completes, but at the login screen I get the infinite beachball of spinning death and can't even type to login. This forces me to do a full restore from my Time Machine. NOTE: I've tried overlay OS installs all these times, not a clean install.
1) Is it possible to update the Vega 56 drivers without updating the OS on a Mac? If so, I'd appreciate instructions of how to do it?
Side question 2 (this is my Mac ignorance):
2) Before I try one more time (this time) with a clean install can I restore from Time Machine without overwriting Mojave even though I have the High Sierra OS in my Time Machine backup? Does Time Machine allow me to only install my other files and not the OS even though it has been backing it all up?