To be certain, you should:
1. Consult your 1980 Corvette's repair manual: This is the most reliable source. The manual will have diagrams showing the sensor's location.
2. Look closely at the thermostat housing and surrounding area of the cylinder head: The sensor is usually a single-wire or two-wire sensor screwed into a threaded port.
3. If you're unsure, post a picture of your engine bay: Someone familiar with these engines can then help pinpoint it.
Remember to disconnect the negative battery cable before working on any electrical components.