If it did turn out to be incompatible, could I use an ordinary SATA to USB link? I do have one of those with a power supply and everything.You'll need to check if your SATA chipset is compatible, if it isn't you'll need an X360 USB Pro.
http://www.instructables.com/id/How-to-JTAG-your-Xbox-360-and-run-homebrew/
http://www.kijiji.ca/v-xbox-360/mississauga-peel-region/black-elite-rgh-jtag-instant-boot-xex-fsd-gtav-files-warranty/1123876483
Thanks for the help!Please don't use "jailbreak"
The thing never was in a "jail"
Nope, if you format the HDD, you'll only lose your saved games/profiles and any other things you didn't copy to the cloud/USB drives.