Lighter was just simply removed, and I resoldered in a Dual USB/Battery voltage gauge from here: www.rspeed.net/USB_Cigarette_Lighter_Adapter_Voltage_Display_p/na0-5820.htm I don’t know how others did it, but I have a video on it, I took the dash off for mine. Just need to take the same points used for the lighter but use them to the new piece, I did a video a while back but can’t recall which one it’s in