Untethered Jailbreak questions

Hello All,

 

So I’ve managed to get my hands on a untethered 5.2 atv2 and I have 2 atv2 boxes on 5.3 tethered. Is there any way possible for me to be able to downgrade my other 2 boxes and do an untethered jailbreak? I’ve tried creating the ipsw using the firmware signatures with ifaith but I have no success. iTunes errors out when trying to restore the atv2 with the custom ipws to the boxes that are on 5.3. Thanks in advanced, all suggestions and help will be greatly appreciated.

 

ThankS!

Cannot be done.  Signatures are unit specific.