I ran mine along the same route as the rear brake light wires.
-Open the gate, pop off the long black strip on the inside the tailgate (pop bottom out first).
-Then pop out the other black panel on bottom right inside of gate. Be careful with this one, the tabs can break easy to just go easy.
-Then pull out the rubber grommet on the outside where the wires go through.
-No run the CB wire on the same path as the brake wire through the tailgate (requires putting your hand in the area of the second black piece you had to pop off)
-Pull the CB wire through the outside of the gate
-Place the rubber grommet back, note where the CB wire is, take the grommet back and snip the corner of it so it will fit around the CB wire.
-Go back to inside of tailgate, zip tie CB wire to brake wire and replace panels.
Sorry, no pictures of all that man.