How to update iphone 3gs from ios 5.1.1 to ios 6?

[taimur_3]

No. MB is the old bootrom. MC is the new bootrom. The new bootrom is tethered/semi-tethered

Thank you Sir. I guess I'll wait for the untethered jailbreak and that probably ask here how to jailbreak and update my iphone to iOS 6.1.3