Acquire a free Xbox Elite transfer cable
One of the things that has been bothering Xbox 360 Elite purchasers is the inability to transfer the files on your current Core or Pro system onto your
little big black beast. Thankfully, Microsoft is temporarily giving away (to American or Canadian consumers only) a data transfer cable that allows you to, well, transfer your files from one hard drive to the new one without resorting to warranty-voiding solutions.
To request this cable you need to own both an Xbox system (Core or Pro) and an Xbox Elite system also, fill out this PDF, and mail it out to Microsoft. For more information on how to perform the transfer you can check out this website.