Black Friday is here and I need a new Premiere 4K editing computer for 2020. Need advice on MOST im

It's time for computer deals and I need a new editing computer badly. I have been limping along with an ancient Mac Pro tower, which I have loved. However, the new Macs are going to be outrageously priced (min of $6K for the entry-level) so it is time to start thinking Windows 10, and this is where it gets sketchy for me.
I need to edit in 4K in Premiere and I use the full Adobe suite. I will also probably use Davinci Resolve for color grading. Obviously, the more RAM and faster striped-SSD drives I use, the better. But when it comes to video cards, which is best? Nvidia? Cuda cores? Do I need two cards for the best performance? How does that even work? What is SLI? I am a creator, not a network admin.

Is there a "best features" editing platform document for Premiere users here in 2019?