@KamsanYoun
Best place to start is to read this:
https://forums.gta5-mods.com/topic/14693/quick-start-guide-to-modding-grand-theft-auto-v

After that, all mods should have installation instructions. Installing mods that require OIV are the more difficult ones and script ones are quick and easy but some get outdated and no longer work.

@Mullac
Use something like 7Zip which is free. You use 7Zip to open or extract the .rar like you would a .zip file. 7Zip does .zip and way more.

@GeneralGrant
Dude no. Do it yourself as mentioned above or pay for it.

@Darth-Elgor
I personally lose interest after a few 1 star ratings saying "ur mod dont work" and then nothing else. Hard to stay motivated when you spend so much time on something just for it to get shitted on because of user error. Then if you want it fixed you have to report it which takes time and it just turns into a hassle really. I also feel like I see more FiveM stuff nowadays so maybe that's why.

@JohnFromGWN
Hate to see you go but completely understand why. Thanks for helping me and others. Stay safe.

@Reyser
I get @JohnFromGWN's post might've been unnecessary but so is being rude towards him. A simple "don't do that" would've been way better. John has been super helpful and one of the few frequent posters on the forum so I don't see the point in disrespecting him.

@JohnFromGWN
Oh ok I misunderstood.
Not sure really but where are you putting "int MyIndex = PaintIndex.Value * 2;" part at?

@JohnFromGWN
Are you wanting to multiply the current value by 2 because yea the multiplier is just the amount it increments by.

@JohnFromGWN
No problem.
What exactly are you looking for documentation on? The EventHandler I found was just by scrolling through the autocomplete menu that pops. I knew of the EventHandlers being a thing I think from back when I used to mess with VB when I was younger.

I used this:

if (Game.IsKeyPressed(Keys.ShiftKey))
        {
            settingsVehicleSpeedRequired.Multiplier = 2;
        }
        else
        {
            settingsVehicleSpeedRequired.Multiplier = 1;
        }

in the OnTick function to let me move the slider faster.

EDIT:
Just an example of what I did.

@JohnFromGWN
Are you using the EventHandler like:
"PaintIndex.ValueChanged += PaintIndex_ValueChanged;" and then just put
"Function.Call(Hash.SET_VEHICLE_COLOURS, LastVehicle, PaintIndex.Value, PaintIndex.Value)" into the new function?

Wasn't sure how you had it all setup but was just curious. Working on a mod now so I'll give this a try and see if I can make it work.

EDIT:
So quick test and it works fine for me using

private void PaintIndex_ValueChanged(object sender, EventArgs e)
    {
            Function.Call(Hash.SET_VEHICLE_COLOURS, Game.Player.Character.LastVehicle, PaintIndex.Value, PaintIndex.Value);
            GTA.UI.Screen.ShowSubtitle("Paint IndexValue is " + PaintIndex.Value, 4000);
    }

Obviously you'd have to check if the vehicle exists and all of that but I had no issues.