What little I know be that apparently usin' any jailbreak firmware be impossible after the 3.56 update. ye need to find a way to get it back down to 3.55.
I bought an E3 Nor Flasher to force me machine back down to 3.55, which supports certain phat models and all slims supposedly. ye can find the info on which flashers support what hardware online.
Put the flasher in yer console, manually update to yer jailbroken firmware of choice, and conglaturations a winrar be you.