I know its late but just in case. You have the 5 pin flat. So I'm guessing you have surge brakes on your trailer. Also 8 wires on 5 pins, most likely 2 brown wires, one brown down each side of the frame for marker/tail lights along with maybe 2 whites for ground wire down each side, then green/yellow and blue. Like this - from http://www.etrailer.com/Wiring/Wesbar/W002290.html