Nice Mod!!! I love to use the hdd to boot my games. Recently i've to change the lens of a drive from one of my good friends. Booting games from hdd save the lifetime of the drives lens.
Well sry to say but if you was so serious than you should be serious enough to find it out by your self but let me help you... Modchips are OUT and Softmod to time will be the Future. So we have a CFW (Custom Firm Ware) for the x360 drives that let us play backups. But M$ dont sleeped and developed a method to pin out such nasty users and BAN them from there Online service. Thats it.