I am using this phone mount, it works great and I have moved it from my 240, is300 and now to the Z34. it bolts to the seat and you can bend it a bunch of different ways. it can get shaky due to the length of the arm but its never really bothered me.
Mega Grip Seat Rail or Floor Phone Car Holder Mount with 18" Arm for iPhone 7, 6S, 6 Plus, 7, 6S, 6: Arkon.com