Hello All,
After a lot of research and some frustration, I was able to apply the update. Here is what I did:
Removed my GTX 970, installed the update. Hung the first and second try because I didn't put fakesmc.kext in a folder named 10.13 in the EFI (Clover). Placing in the Other folder didn't work for me, so I installed the latest Clover, which added the 10.13 folder.
After the update, reinstalled the GTX 970, which resulted in crashing and boot loops. Booted to single user mode, removed all Nvidia driver files, still boot loops. Removed the GTX 970 and started some research.
I followed post 74 of this thread. I'd already installed the latest Nvidia driver (manually after downloading using the link from post 1 of this thread).
Reinstalled the GTX 970, still boot looping. Uninstalled the GTX 970.
Rebooted with Intel graphics, then set the Nvidia driver to use 'Default macOS Graphics Driver' as specified in post 76 of this thread.
Reinstalled the GTX 970 and was able to boot the system. Set the Nvidia driver to use 'Nvidia Web Driver' then rebooted the system. Good to go, save onboard sound not working, which I don't need. Sleep = OK, but I have to hit the keyboard twice to get the logon screen to display (starts up on first key pressed, won't activate display until second key pressed).
This post is fairly brief, but it took a lot of time to get where I am. I dealt with the 'printf' issue as well. Good luck to everyone, and don't be afraid to try hybrid approaches from the information in this thread.
PassiveO