However, to be absolutely certain, you need to:
1. Consult your owner's manual: This is the best source for your specific truck's location.
2. Check a repair manual (like a Chilton's or Haynes): These manuals have diagrams showing the precise location of the oil pressure switch for your specific engine.
3. Look online for diagrams specific to your engine: Searching for "[Your Engine Size] Chevrolet Oil Pressure Switch Location" on Google Images can provide visual assistance.
Without knowing your engine size, I cannot give you a precise location. Looking at the engine itself, near the oil filter, is the best way to find it after using the resources mentioned above. The switch is usually a small, cylindrical component with one or two wires connected to it.