Print

[82_Z28]

you should be able to run off the dvd assuming you install the mod correctly.
its always a good idea to test the game on your hdd first, then make a iso out of that folder.  
your method may get pretty hard to do.  Since you don't have ftp access, you can't get the files to mod.

one thing you could do however, is burn the .scm file to a dvd in Xiso format so your xbox can read it, then access the dvd with boXplorer, and replace the old one (after renaming it and making a backup of course)
one thing that you should know though is some pc script mods have issues, some work, some don't.   I think i remember hearing this does though.