This tool will help modding easier and faster without modifing system file or any regenerate tool. It similar to PES series's Kitserver if you ever used.
Download : Version 1.0.0.2 full
How to use : (please take a look inside "Docs" folder included)
Example file (extract to "Fifa13mod") : http://www63.zippyshare.com/v/40346354/file.html
This's beta version. It's working fine on my PC but I cant guarantee for other environments.
Have a happy modding.