You need to point redsn0w to an iOS 6.0 Ipsw to jailbreak 6.1.3 (redsn0w hasn't been updated to recognize any iOS 6 firmware other than 6.0)No, what does 6.0 have to do with it? Don't I need 6.1.3 ipsw?
Pretty much. If you're relying on a software unlock (ultrasn0w), make sure to make a custom firmware that is a no baseband upgrade and restore to 6.1.3 with that custom firmwareOK, so correct me if I am wrong...
Device currently has 4.1 and I want to go to 6.1.3 untethered.
1. upgrade to 6.1.3 normally thru itunes
2. get the newest redsn0w
3. download 6.0 ipsw for 3gs
4. open redsn0w and point it to that ipsw
5. put 3gs in DFU mode and jailbreak with redsn0w