Hi Spark, I have a 2005 2500HD 4×4 with a 6.0L engine. This truck has manual locks and windows and has never had cruise control. I am aware that in some cases the wiring for cc is sometimes provided, but that is not the case with my truck. I already have a multi-function switch with the cc option. I stumbled upon your article for adding cruise to a 2005 silverado and clicked on the links that brought me here. What I am in need of is the locations and pin numbers for the 4 tie in points from the harness of the multi-function switch.