7 Pin Light Plug Wiring. You were looking for the wiring diagram/colors for the truck connectors instead of the trailer plug wiring. Dark green/Red stripe is your left turn signal and brake light Brown with pink stripe is your right turn signal and brake light.
You could always have someone wire the rear lights so there is power at the bottom of the bumper. The high mechanical advantage of long handles and short jaws means that they can easily snip through light to medium gage wire used in electronics. Watch the brake controller to ensure those scary warning messages don't pop up.
This accounts for three of the colors in the wiring harness.
The left and right turn signal lights should each have a different color.
I drew this crude diagram to help explain. There should be a common color for both the tail lights. Black and blue wires are not connected in the above image as they were not In my personal experience the flat style plug is more reliable.