See Figures 1 and 2
The Vehicle Emission Control Information (VECI) label is located in the engine compartment (fan shroud, radiator support, hood underside, etc.) of every vehicle produced by General Motors. The label contains important emissions specifications and setting procedures, as well as a vacuum hose schematic with various emissions components identified.
When servicing your Cadillac this label should always be checked for up-to-date information pertaining specifically to your car.
Always follow the timing procedures on this label when adjusting ignition timing.