Ok to start, you need WinXIP not WinZIP or WinRAR, this is the program used to edit the .xip files that UIX and the m$ dash uses.

Start by FTP'ing over your \user.interface.x.dash\xips\default.xip over from your xbox.

Next run the program winXIP, then go File -> Open
Open up defaut.xip

You will get a bunch of config.xap, default.xap, dvd.xap, etc...

The 1 we are looking for is default.xap
Click on it and go edit -> extract

Extract it to the desktop then open default.xap with notepad, yes notepad...