Weapon Scroll HUD Help!

A little background on me, soon I hope to create a Garry’s Mod Gamemode which has DarkRP aspects but is more like Arma 3 life. I would first like to achieve this by changing when you scroll that selecting weapon bar to something more… Realistic! I am semi-new to this and am wondering whether it is even possible to do such a thing. Pointers on what to do and whether it is possible will be greatly appreciated! -Matt