I was going to make a comment, but I said to myself, 'never mind.' As for general knowledge base for the board, GM Designe its wiring systems so that it's impossible to plug the wrong wire onto the wrong thing.

With that hokeyass mess in the picture, I wouldn't have a clue. Everyone does things their own way. I would pay ten times the price for a used harness than buy the problems-waiting-to-happen when you use the painless, also refered to pita, harness.