http://forum.xda-developers.com/showthread.php?t=3427441. Download SoftSPL by the-equinoxe.
2. Download the IPL/SPL based on your device and carrier(attached below)
3. Extract SoftSPL to its own folder and then extract the nk.nbf file from the correct IPL/SPL to the SoftSPL folder.
4. Run Start-sSPL.exe and follow the simple directions. It is almost fully automated(your screen will turn white during the flashing process and it will appear to have crashed. This is normal so just proceed like normal)
5. HardSPL should now be removed if everything worked properly. Depending on your device and Carrier, download the appropriate Rom for your device: