How to go about this scenario?

[vong]

Greetings,
I am currently on iOS 4.2.1 with BB 1.59.00 on my iPhone 4. I am looking to upgrade my phone to iOS 5.0.0 but I want to maintain my baseband. I am NOT looking to jailbreak it, I will just wait for untethered (if it does come out). If I do plan to update my iPhone to iOS 5, how would I do it?

Thanks.

 

[maturola]

Create a custom IPSW using Pwnage tool and upgrade to that, however Apple just release 5.0.1 and based on some rumors it had already stop signing 5.0 so YOu won't be able to upgrade to that. Best bet is to wait a bit for for info to come.

 

[vong]

Okay, just download redsn0w. Opened up the app, went to extras found iPhone 4 iOS5 IPSW

Edit: Read the pop-up that showed up. All I have to do is put my Phone into PWNED DFU mode and use this new IPSW and I am good to go?