Setup:

1. Open Documents -> My Games -> Far Cry 4 -> *UNIQUEID* -> GamerProfile.xml

2. Search for "FOVScaleFactor" and change the value to "1.0275".

3. Create a backup copy of these files:

Far Cry 4\bin\FC64.dll
Far Cry 4\data_win32\patch_hd.dat
Far Cry 4\data_win32\patch_hd.fat

4. Copy the Far Cry 4 folder from this mod over your game's installation directory, replacing the files.