I just received my LED Door Sills for my 2020 GMC 2500HD Denali 6.6 Duramax! The Door Sills are plug and play and were just released by GM for the New Next Gen GM Trucks(2019 1500 and 2020 2500). The same connectors exist on these Door Sills(one plug / 2 connectors and one ground connector on the passenger side of the wiring harness) than the earlier version GM Trucks. The main difference in the LED Sills vs. the earlier GM Models is the LED Sill is an insert into the existing sill where the earlier version LED Sills were a complete replacement of the original / entire sill.
I have not installed the sills yet, however it looks like maybe a 1 to 2 hour job as I will need to run the wiring harness behind the front dashboard / kick panel from the passenger side to the drivers side where the harness plugs into the BCM / Dome light circuit.
I'll post a pic when install is complete.