How to Auto Install a DEB File Using Cydia

If you do not have a Cydia folder in the /var/root/Media folder, you will need to create one.
If you do not have a AutoInstall folder in the /var/root/Media/Cydia folder, you will need to create one.
Drag the DEB files
Once fully copied all you must do is power off and on your iPhone, twice! You will then see the applications installed on your Springboard and in Cydia Installer.
Alternatively, you can power off once and then respring.

Change carrier logo without winterboard

Try in
/System/Library/CoreServices/SpringBoard.app - didn't change

Also try it in /System/Library/Carrier Bundles/ATT_US.bundle


Try:

/private/var/mobile/Library/Carrier Bundle.bundle

use Make It Mine is Cydia to change your carrier name to ATT