as you stand in front of the car & look at the engine,(older type 1.3 engine), it's on the left of the engine next to the rocker cover, inside the alloy casting that may have a thermostatic switch on top of it & wires attached to it. it's held in place by two 13mm bolts. it also has the radiator hose attached to it. you may also need a new gasket if replacing the thermostat.
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