Originally Posted by Dubstep
You will only be able to go to 4.3.3 because you dun have SHSH blobs for 4.2.1 or 4.1 download sn0wbreeze and use it to make a custom firmware without a baseband and restore to that firmware in iTunes. Your phone will already be jailbroken and unlocked and on the same baseband just higher firmware. Alternatively you can just google "custom 4.3.3 firmware no baseband" and just use that. I'm assuming you know you to dfu restore and point iTunes to a custom firmware. If you need more detailed instructions just ask.
Ok thanks. So I can follow these instructions
and it'll work?
Also when I restore to the custom 4.3.3 firmware, will all my music, videos, photos, apps, settings etc stay on my phone as they were before?