Outer Limits 4x4 Board

I want to wire a reverse lamp onto the back of my ute so that when its in reverse the
light comes on but only when i have the tail lights on (ie at night).

If i was to do this, would i put a wire from the tail light and the reverse light to a relay
then to the lamp or from the headlight switch under the dash to the reverse light and then the relay and lamp?

If some one has done this, are you able to put a wiring diagram of how you did it.

Cheers

yeah thats how you can do it wire from tail lights to pin 86 and the wire from reverse to pin 30. if you were worried about to much load on the reverse circuit you could run a wire from tail lights to pin 86 then a power wire to pin 30 then your output pin 87a would the go to pin 30 on a second relay and then the wire from the reverse light to pin 86. you could also wire an on/off switch in with a couple of diodes to stop feed back so you could turn your reverse lamp on at night if you needed it on with the car running and not in reverse