Need help installing newer graphics driver

I have a Clevo P370sm3 with 970m sli and Prema Bios and I cant seem to install newer drivers for the graphics cards. My current version is 353.82.

I have tried installing them from Nvidia website and nothing works. I know I need to modify a certain file, I did this before but it was many man years ago, I know its a INF file.

My current specs are below,
windows 8.1 64bit
17.3 inch screen the 120hz version
i7 4710qm
16gb ram 1600mhz
970m sli
17.3 inch screen the 120hz version
x2 2tb 5400rpm...

Need help installing newer graphics driver