No programing is needed.
No harnesses needed.
No switch is needed.
You can use any 12v led light, not just mopar.
All you need to do is identify the wire that supplies power to the cargo light.
It is accessed through a removable panel in the left rear floor. It's in a large bundle of wires running front to back.
Don't recall the color. Some say its white with tan tracer. You can pull your cargo light to verify.
The other beauty of this approach is NO switch needed, as they'll automatically turn on and off with the tailgate!
Easy peasy