1, get your mw3 savedgame from your xbox360 harddrive with a USB or TRANSFER CABLE.

2, Plug your USB into the computer and load horizon.

3, if you know how to mod with modio it is the same with horizon

4, download this link for the modded gpd
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when you extract it it will ask for a password it is OGZxFTW


5, in your savedgame you need to change the id and console id into the modded saved game.

6, Rehash And Resign.

7, remove the original gamesave from your usb or transfercable and drag in the new one.

8 do not put this mod on your harddrive because it will mess up. just load mw3 go to campagin and soon as it loads and you can move save and quit and go on to spec ops or survival mode

Video Tutorial:http://www.youtube.com/watch?v=IoKg0MfpTbA