Downgrade before or after unlock?

[buckdog05]

I have two iPhone 3g phones that I would like to downgrade to IOS 3 and unlock. One is currently on 4.2.1 and modem firmware 05.15.04. The other is on 4.0.1 and 5.13.04. Should I downgrade to iOS3 before I unlock the phones or after I unlock the phones?

I was planning on using this guide for downgrading.

Also, is there something special I need to do to not loose GPS when I unlock? From this page, it looks like I might loose GPS on the phone with 4.2.1 but not the phone with 4.0.1. Is this correct?


Thanks!

[swip51]

make sure it is an old bootrom before you do anything!!!!!!!

If it is new, trade with someone for an old so it doesn't wipe your baseband.

First of all just jailbreak the 5.13.04 and unlock it then make a custom using snowbreeze (baseband preservation) and put whatever you want on there.

The 5.15.04, flash the baseband and jailbreak where it is right now using an older version of redsnow, then do the same, (snowbreeze) to whatever ios you want to run

[buckdog05]

make sure it is an old bootrom before you do anything!!!!!!!

If it is new, trade with someone for an old so it doesn't wipe your baseband.

First of all just jailbreak the 5.13.04 and unlock it then make a custom using snowbreeze (baseband preservation) and put whatever you want on there.

The 5.15.04, flash the baseband and jailbreak where it is right now using an older version of redsnow, then do the same, (snowbreeze) to whatever ios you want to run

Thanks!