I have a 99 XK8 Convertible and am changing the radio. I have the 1999 XK8 Range diagram for the entertainment system but do not know if this is for British or US cars. All it says is Driver Side and Passenger side. Anyone know?

 

Are you talking about wiring diagrams? If so, Driver's Side and Passenger Side refer to whatever car you are working on as items labelled as Driver's or Passenger Side move from LHD to RHD cars. Items that are labelled Right or Left don't move between LHD and RHD.