Alienware M18X R2 upgrade (lazy and actual guide)

I see many people have sold their Alienware laptops and got new Eurocom, Clevo etc. Well, I'm the lazy guy and thus I haven't sold mine Alienware M18X R2 Nebula Red yet. Initially it came with i7-3610QM CPU and AMD 7970M CrossfireX, 8GB RAM. After 2 years of using both GPUs have failed and I decided to get a replacement. It was difficult to choose a new GPU but now I have both Nvidia GTX 970M and 980M. Also, I got i7-3940XM CPU and 32GB RAM, SLI cable for future experiments.
I think AW M18X...

Alienware M18X R2 upgrade (lazy and actual guide)