See the bottom of the attached diagram. You have power going in on C287 pin 4 then out on C287 pin 7, and the other bank of lights are power in on C286 pin 8 and out on C286 pin 7.
Next if you look up at the connector listings toward the left side of the diagram:
C287-4 = Red/Black wire (which connects to same color wire C286-8). Power.
C287-7 = Black wire (which connects to same color wire C286-7) Ground.
"Power" above comes from the interior lights circuit. You can find that and associated diagrams linked in my sig below. Ground, just check resistance to any chassis ground (most unpainted bare metal areas).