I know it’s been almost a year but if your still looking for that switch panel they updated the switch panel part number. It’s 84347210. They are about $55.
https://www.gmupfitter.com/files/media/photo/761/Sierra_Silverado_Electrical_Body_Builders_Manual_Service_Manual_2017_en_US.pdf
maybe this will help. headlight schematics start on page 56