Credit to it's original developer...
http://forum.xda-dev...d.php?t=2596175
Finally managed to unlock GSM part of LG G2 LS980
Root Required
Install Rom Tool Box Lite
Run Rom Tool Box Lite and select Build.prop editor
ro.carrier=spr (NOT SPR) ro.build.target_operator=spr (NOT SPR) persist.service.crash.enable=1
save, exit and reboot.
Its as simple as that.
GOT THE DATA TO WORK
Install Telinfo from playstore and use it switch between GSM SIM and CDMA NV