To find it, you'll need to:
1. Identify your exact engine: Look for a casting number on the engine block. This will help pinpoint the exact year and model.
2. Consult a repair manual: A Haynes or Chilton repair manual specific to your year and model Chevy will have diagrams showing the location of the oil pressure sending unit. This is the most reliable method.
3. Use an online parts diagram: Many websites (like AutoZone, Advance Auto Parts, etc.) have online parts diagrams. You'll need to enter your vehicle's information to view the diagram.
4. Look near the oil filter: It's often located near the oil filter, on the side of the engine block. It's usually a small sensor with one or two wires connected to it.
Be careful when looking for it; the engine is hot after running and some components may be under pressure. Let the engine cool completely before working on it.