INSTRUCTIONS: downgrade to GB (if you didn't already, look HERE), install any stock based ICS rom in recovery, flash this zip and reboot.
NOTE: If you are using any stock based ICS rom (like Stock Plus, Lightning, Infusion, B952-slim, etc), you can install the zip to downgrade to GB (look HERE) and then install the zip to use ICS roms in GB. You don't need to make wipes or reinstall the rom, just flash those two zips in recovery and reboot. I think this method is better than relocking the bootloader.
Edited by jsevi83, 12 March 2013 - 03:17 AM.