i saw this post in the precision mods forum, and i was wondering if you can confirm this working. well, here it goes:
Boot your XBox WITHOUT the Live disk. Connect to your XBox via FTP. Rename the file called xboxdash.xbe to xboxdash.evo or something you can remember for later. Next, rename the msxboxdash.xbe to xboxdash.xbe and disconnect FTP. Reboot your XBox. It will be at the default settings with the MS dash. Then load the Live disc. It will replace xboxdash.xbe(Default one) with xboxdash.xbe(with Live menu selection one). Install your settings, etc. Reboot your XBox to confirm the change. You should have the Live menu. Now, take your EvoX bootable DVDR listed above and boot it. You will then see the EvoX dash. Connect to your XBox again via FTP and rename the file called xboxdash.xbe to msxboxdash.xbe and rename the file called xboxdash.evo to xboxdash.xbe. Reboot your XBox and confirm that you can run the Live menu by choosing MS Dashboard, then press A. You should now see the Live menu and when you reboot, it should start the EvoX dashboard.