CHEVROLET S-10 - Manual (Page 269)

Checking Coolant The coolant recovery tank is located in the engine
compartment near the passenger side of the vehicle.
See Engine Compartment Overview on page 5-12
for more information on location.
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at ADD, or a
little higher. When your engine is warm, the level
should be up to FULL HOT, or a little higher.
5-25