SecLauncher3 is located in priv-app if you need a copy
@Jessooca has a thread dl from there.
I use apktool2
@The Sickness has a well written tutorial on apkmanager
http://xdaforums.com/showthread.php?p=50663679
Google search both apktool2 and apkmanager just to see what is best for you ( imo apktool2 is the way to go ).
After that set up your environment then refer back to my first post so you can use the link to help guide you. It is a lot easier to understand it when you have the files in front of you.
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