How do i install the HD Content for Battlefield 3 on an xbox 4gb?

cant install the HD content from battlefield 3 as my 4gb xbox only has a memory unit instead of a hard drive, is there a way around this? Can i hack a pen drive to make it the hdd on my xbox?|||you can buy a 20gig regular xbox 360 hard drive for $20 and look on youtube for a tutorial how to remove the hard drive from it so it will work in the slim.|||You don't have to "hack" anything. A standard USB or external HDD can be used as a storage device for the 360. Simply plug it in, go into the memory on the dashboard, and configure it to be a storage device. You can use up to 16GB on any standard USB drive. Keep in mind it will format your drive, so if you have information stored on it you may want to back it up.|||get a stick drive that's around 2-3gb format it on your computer then plug it in and the Xbox will ask you if you want to format it for use by the Xbox. just hit the A Button and wait a while and it should work fine.