Or just get a GDEMU for $40 and play the .GDI's from all regions already region free. I realize if you want to run from discs this is not the solution you want to hear. But GDEMU has built in region bypass and with GDMENU you can toggle the VGA flags directly from that app on your PC when building an SD card image. So it kinda is related to what you want to do. No need to solder a new bios chip to the console. Just have to open the system once and remove the disc drive and put the GDEMU inside and you are ready to go.