^^I did it in 2 minz.lol.
You just need a programmable usb chip. but if you by accident update. you cannot downgrade(since lower firmware is required to run backups)
but one team has managed to find a downgrader which people are working on to find a free solution.
So like i said either buy a 3.41 ps3 and do not update(means no online play) or JUST update and play online and buy the "specific" ps jailbreakdongle(100 dollars) to downgrade whenever you want to run backups(does require transferring all ur games back) since it wipes the harddrive.
or JUST WAIT(there will be a free solution for ANY FIRMWARE.) soon