There's probably an adjustment on the *position* of the switch relative to the clutch pedal. You want to make sure that the switch is POSITIVELY CLOSED when the pedal is depressed, and OPEN when the clutch pedal is released. If your adjustment is 'just barely closed' when clutch is depressed, then the switch might have a resistive connection, which would make it heat up with the current thru it??
With the key and power OFF, can you measure the resistance across the switch based on clutch pedal depression? Do you FULLY depress the clutch pedal when starting the car?