need help flashing lite on DG-16D4S 9504 PCB

hey guys, i have been thinking about flashing my lite on DG-16D4S 9504 to lt 3.0 since my current drive only can play XDG2 Games that are burned,I have a unlocked pcb in my dvd drive bur not sure what firmware it and i dont have the dvd key from the original pcb so is there anyway i can get my key from the unlocked pcb board and then flash it to lt 3.0 or is it impossible if i can then what will i be needing,

i have researching about this like 1000times but not found anything so i just...

need help flashing lite on DG-16D4S 9504 PCB