2015 Access cab speaker add-in HOWTO?

I'm going to change out the speakers in my 2015 Tacoma and since I was already there I figured I would add in rear speakers too and fish the lines up to the head unit for connection when I change it out this fall.
I am playing hell finding a HOWTO or tutorial, or a video of *anyone* doing this. I know the speaker mounts are there, I've seen that in a video, but nothing about where and how to run the cables, holes for the same, tolerances, etc.
Does anyone know of a tutorial on adding in the rear speakers on a 2015 Taco Access Cab?

 

I don't recall, but the Sticky Thread " DIY: Basic Speaker upgrade, 2ND GEN ACCESS CAB" at the top of this Audio Video forum may go into that ?