Hi guys and gals

I have a question, I've seen some XJs where the turn signals light up with the headlights, how does that work with a different relay in the system or something? I know its an odd question but I want to turn my European spec XJ into US spec, including seats, lights (side markers and turn signals and rear lamps), but keeping some of the European features like small turn signals on the fenders.

any ideas or help people?

many thanks

Joey