I tried to do the same thing, and I also failed. It just keeps telling me the new file doesn't have permission to access "C:\Program Files\Grand Theft Auto V\mods\source." It's the first time when I tried to mod this freaking game. Everyone on youtube keeps saying that it's so easy to mod it. And here I am. Who could even mod the gta 5 for android. The worst part is that I'm doing everything exactly like in the youtube tutorials. However, it just doesn't work out for me! I can't understand what I'm doing wrong.