Help Cydia not showing up 3GS old bootrom 6.15.00

[sunga33]

I jail broke my friends 3GS old bootrom using jailbreakme.com. Then I installed iPad baseband. Now Cydia is not showing up and can't download ultras0w. Shsh not saved. I don't wanna restore to 4.3.5 because of iPad baseband. Any suggestions?

[i.Annie]

Download Sn0wbreeze 2.1
Download stock 4.1 ipsw for iPhone 3GS

Open Sn0wbreeze, select 4.1 ipsw, create custom firmware
**note** if you don't have an official SIM to activate with, in General, checkmark the "activate" box, if you do have the SIM, make sure the box is unchecked
Sn0wbreeze will prompt for DFU when finished creating cFW, do so
Open iTunes once in Pwned DFU mode
Hold shift, click restore, select custom 4.1 firmware
Allow for restore to finish and you should be able to access the springboard if you created an activated version. If you did not create an activated version, you'll get the emergency call screen in which you will then use the official SIM to activate with in iTunes.

Cydia should then be on the Springboard, open it and install Ultrasn0w