I hooked the signal harness to this. At first I thought it was the rear brake signal, but when I hooked it to the brake light the rear brake still didn't light it up.
This one is for the ignition mapping switch. Not needed unless you have the switch.
For the rest of them, follow the colors in your wiring diagram and it will all make sense. The small white ones are for turn signals. The picture of the wiring harness in the parts diagram is also useful. I did the same thing last year and went through the same process.