After beating my head against the wall some more I figured out why my NVidia drivers were installing incorrectly. Disabling UEFI in BIOS seemed to do the trick, and hey! Suddenly I could install the latest graphics drivers via driver manager (with the proper PPA added)!. I now have Steam installed, plus Waterfox and some of the basics. Even got the Steam Controller udev rules sorted. Now I’m finally ready to test games on another computer and have a more portable version of Linux.
Now I’ll just need to remember to enable and disable UEFI when booting between Windows and Mint… ugh. :rick: