[Frank Messina]

Do you know what the number of your car is? Tell us a little more about your car. FI or carb, donor build, etc. The kit originally came with a toggle switch only for the fan, but it became popular among builders to add a thermostatic switch for the fan and to use the toggle as a manual override. That way the fan would come on when it was programmed for but you had a backup in case of an emergencey. There are a number of thermostatic switch types available, one clamps to the upper radiator hose, another uses a probe through the radiator fins, and still another screws into the water crossover in the intake manifold. They can be either fixed or adjustable, your choice. Not sure how long you've owned your car but you may want to call the previous owner/builder and take some notes on how it was built.
Frank