3GS 3.0.1 upgrading to 4.1

[iphonelafayette]

Have a 3GS 3.0.1 unlocked/jailbroken . No shsh files saved. trying to update to 4.0 or higher keeping my baseband / modem firmware at unlockable 4.26.08 . Tried making custom firmware with pwnage tool for 3.1.2 / 3.1.3 /. And failed . Only version I could create was 4.1 ( pwnage version 4.1.3 unlock). Thanks!!!

[iphonelafayette]

How do I update and keep the unlock?

[Simon]

Just use pwnage tool 4.1.3 to make a custom 4.2.1 and restore to that in itunes. Make sure you say no to the ipad baseband part so that your baseband is preserved.

[iphonelafayette]

When I try to make the custom firmware if says invalid version.
I am in advanced mode and choose the stock 4.2.1 firmware

[Simon]

You need to manually add the 3GS 4.2.1 bundle as outlined in update 3 on the dev team blog first: Dev-Team Blog

[iphonelafayette]

Thanks for your help xcar.. Could you explain how to add that bundle on pwnage tool . I do not see where to add this . Thanks

[Simon]

You get the bundle from update #3
Then you can follow this to add it: iClarified - iPhone - How to Add a Firmware Bundle to PwnageTool