So. Unlock his 80G disk on your Xbox and set it to one side. Get a clean Krayzie 1.1.1 gamesave set, and use your Xbox to transfer the gamesaves to your memory card. Put his original disk back into his Xbox, and transfer the gamesaves across.
Make sure the dash on his Xbox is version 5960, and if it isn't you need to update it. The easiest method is to cold boot using a recent live enabled game to restore the dash. Halo 2 and Doom 3 definitely work (I've used them both), and Pro Evolution Soccer 4, Need For Speed Most Wanted, and Goldeneye Rogue Agent should work (Live enabled, 2004 or later). You just go through the motions of connecting to live, and the first thing the game does is update the dash. Alternatively you can use the method in
this post.
Once that's done softmod his Xbox with Splinter Cell. Choose Basic install - UnleashX dashboard.
When it's working you can use Chimp to set up the 80GB disk on his Xbox.
Edit: You could have posted
here, as your original problem was with a gamesave exploit, or
here as it's a General Hardware / Technical problem.