Requirements
-USB
-CoD MW3
-Modio
-Mw3 offline editor

Step 1-Go on Mw3 and start up a offline game, kill your self one time
Step 2-Go on your storage on xbox and move the multiplayer progress to your usb
Step 3-Go to Modio and click on open save, usb, then on your profile and on the save
Step 4- Click on advanced, then on edit package contents
Step 5- Move that save to your desktop
Step 6- Open the mw3 editor and mod whatever you want on the account
Step 7-Save your game save
Step 8-Go back in Modio, Right click on the save and add the file you just modded
Step 9- Click done and save changes two times
Step 10- Go back to General and your profile should be below, click on it and there should be a window popped up and then your all done


Link for mp editor
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Link for Modio
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