AlaskaTrip

I’m trying to find instructions for how to install a set of illuminated door sill plates for my 2023 GMC 3500HD Denali. The GM part number is GM#85136964 I found all sorts of instructions for other models. But can’t find the one for this. I can’t figure out where to connect the wires on the drivers side under the dash. There is one specific wire I’m supposed to cut and splice this harness in to but I don’t want to cut the wrong wire . Anyone have access to GM Service Information (S.I.)? Thanks for the help!!