There is not a single harness for 2019s, the harness depends upon your configuration, for example what speakers do you have, what other 'features' do you have that depend upon hardware in the door that needs to be connected (via wires) to the main wiring in the truck. You need the harness part number for your specific 2019 configuration. Or as MannyHen did, run your own wires (2) from the new handle through the door to the chassis door connector.
Per FedEx my parts are to arrive today
- originally I was going to run a wire and save some $s, but ended up ordering the harness (that then ended up causing a total screw up with my order and delay).
For a BigHorn, Level 2, 6 Speaker (or 9 I believe, but not the 19), 68360301AD is the Driver harness - at least that is what I ordered, so should find out this weekend.