Are you looking for the “pass-thru” wires for the upfitters?
I have a 20, and they may differ slightly, but the location area should be the same.
I would start looking on the left side, by the fuse panel
underneath the glove box.
You need a trim pry tool, and carefully pry off
the plastic moulding by the passenger side to gain better access.
***Note: The pass thru wires are not “hot” or powered by upfitter switches by default. It needs to be connected to matching wires under the hood.
(this differs which side, left or right you might find yours...see pic)
***Also, they are kinda hard to spot. They will be looped and tucked
in, and taped on a side of a wire harness. Start by looking for
exposed color wires that matches the upfitter colors.
Gently pull one, til you find the blunt ends.
Thats how I found mine.
Remove fuse cover and plastic trim to see better and gain access:
Under Glove box, by passenger foot well:
Under the hood, behind battery: