I found this on MAXCONSOLE forums. I myself am going to do this after I beat the game. I have the 1.60GB version of Splinter Cell on my MS now, but after I get do the Extreme Rip, I'll be able to get another 3-4 ISOs on my 4GB MS. That will have to include Cars - Looks fun!
By the way, the easiest way to dummy files (instead of creating them on your own and then placing them in the corresponding folders) is with YAUIS (Yet Another UMD ISO Shrinker) found here:
To dummy, double click the YAUIS.exe, let it open up, drop the ACTUAL ISO itself into the blank window, click the right tab at the top, (can't remember what it's called) and double click the Disc icon. Go thru the folders, find all the corresponding elements you want to dummy, right click on w/e individual file you're dummying then click delete. By clicking 'delete', it will actually 'dummy' the file.
Hope some of you can use this. If you can't send hate mail to: