Once you specify the engine, you can then:
* Consult your vehicle's repair manual: This is the most reliable source.
* Use an online parts diagram: Websites like AutoZone, Advance Auto Parts, or Napa Auto Parts usually have diagrams you can search by year, make, model, and engine.
* Search online forums: Searching for "[your engine] 1997 Chevy truck camshaft position sensor location" on forums like Chevrolet forums might yield pictures from other owners.
Without knowing the engine size, providing a precise location is impossible.