Just want to thank everyone in this thread for the info ! I ordered the GM Part 13581082 as listed in this thread. I followed the instructions and installed this in less than 30 minutes in my 2019 Silverado 1500 RST. The plug was glued in the ceiling pillar as noted and I had to use a flat head screwdriver to pry it off the metal, but it works like a champ. Still not sure why this is not included in a truck that costs as much as it does, but the upgrade was easy enough.