Hi guys. I was hoping to change my brakes today while my wife has the kids. I called around and hardly anyone carries pads in stock for my 99 XJ8. Finally I called autozone and they said they have one pair but it is for the ATE callipers. How do I know which I need? I thought they would only have one size. And I will be driving this car to pick them up so I can't take the others off yet. Thanks.