: Get the FC3 Mod Installer from the official Far Cry Modding site.
: Unzip the Mod Installer into a folder on your PC.
Select Far Cry 3 and direct the tool to your game's bin folder if prompted.
: Copy the new modded patch.dat and patch.fat files into the data_win32 folder. Recommended Sources Far Cry 3 MOD IT! 3 : How to Install Mods