There was (mouse nest) insulation all across the front on the roof seam.
At first I though mice?
It was neatly placed all the way across the front channel.
So this is what the factory done to hold the cab light wire in place and protect it.
Because some of it was still bonded to the wiring harness.
Driver's side sunvisor reinforcement plate
and hole for routing cab light harness.
Pass. side sunvisor reinforcement is there
so A visor could be added.
Because this truck didn't come out with one.
This is the last terminal on the cab light harness.
Here's a picture of the Insulation
from pass side view.
.