The diagram would not show spare wires. It would be diagramed out in the schematic with a note stating " optional " or " Suburban, Utility" something to designate if it was a model unique installation.
Yes the diagram is your map , but you really should trace where that orange came from to identify where it should go.
The only wire taped bundles from factory generally , we're Camper lighting power( in left stake pocket or under left front bed ) , and trailer wire bundle ( taped up under bed near license plate.