creating custom resolution, manual timings help

Hello,

i use program for interpolating frames for video playback and i have framerate drops. I need to get closest as possible to 119.88 hz.

But in nvidia control panel, i can't adjust hz by fractions, if i use automatic timing profile. I need to edit timings manually. Problem is i already searched many times and found nada. I have monitor Eizo Foris fg2421 1920x1080 120 hz. Here is my screen shot from nvidia control panel.

I tried cru aswell, but wasn't able to get close to 119.88 hz. If someone could link me guide how to infer these timings, or tell them to me i would appreciate it !