Adding a backup camera to a 2005

Hello,

Hopefully this is the right section for this. I have a 2005 X-Runner that I put a 2014 touchscreen non nav, non entune radio into. I wanted the OEM look with bluetooth streaming music. I'm looking to add in a backup camera to the tailgate handle but i noticed a lot of them use the yellow video plug.

Is there a way to...
1. Add a yellow plug to my OEM 2014 head unit and use an aftermarket camera - I saw there was an Axxess AX-TOYCAM3-6V that adds a yellow plug into the oem harness and was wondering if anyone had an experience with this item.

or

2. Add the OEM wiring to the truck and run the wiring the length of the truck and use an OEM camera in the tailgate - Is it even possible to buy the "plumbing" to add to an older truck that didnt have it? I understand the newer model 2nd gens had the wiring already ran and all that needs to be done is to buy the handle/camera and plug wiring in.

Anyways thanks in advance!