How to convert LG optimus G Korean version to international

1. Download international firmware >>> Click here
2. Download KDZ updater >>> Click here
3. Extract 'KDZ_FW_UPD_EN.zip'
4. Connect your phone to PC on download mode (Turn off the phone, press and hold volume up and down button together, and connect phone to PC)
5. If you are using windows 7, open 'Windows Enabler.exe' and click it once (in tray)
6. Run 'KDZ_FW_UPD.exe'
7. Make sure to use these settings
   
8. Browse and select kdz file you have downloaded in first step 
9. Click 'Lunch software update'
10. Done, Your Korean phone is now converted to international version

Note: You may face signal loss problem after flashing international firmware. To fix that, you have to flash Korean base-band to your phone.