I have a 64gb Sprint iPhone 4s and I'm looking to switch to Verizon. My girlfriend gave me her broken, but usable, 16gb Verizon iPhone 4 now that she upgraded to the 5. What I am looking to do is to take the ESN (and/or whatever other IDs i may need) off her iPhone 4 and put it on mine so I can activate my phone on Verizon. What software/tools can do this for me? Is there a tutorial on how to do this (not that I'm incapable, but tutorials save time and reduce the likelihood of errors)?