A Friends Lexus (2016 RX200) has a subwoofer in the rear hatch.... My 2018 doesn't (at least there is no cut out in the plastic so i ASSUME it aint there). Possibly an "option" with a certain radio package ?? (which I didn't get). Question... Is it just the speaker itself that is missing??? (Does Lexus use the same radio etc)... Again, I'm assuming the wiring is there... hate to pull it all apart and find there is no amplifier built in to drive a sub. Thanks...