Can't speak to the harness you mention, I too used the Cooltec harness. Follow the directions (I also found a U-Tube video on the install), take your time. Not difficult, relatively easy access to the connection point (remove a couple of interior trim panels) and less than 1/2 the cost of the Mopar harness.
Jay & Peggy Monroe with Dolly
Can't take it with you - don't plan on leaving any behind
2016 Newmar London Aire 4553, Spartan chassis
2020 Jeep Wrangler toad