Hello, I am seeking advice from those who have used magnetic engine block heaters. I know many use some kind of apparatus on their vehicle. My interest is finding a "this winter" fix for my small farm tractor. I thought a zerostart magnetic heater rated at 200W and thermostatically limited to 250F may be a safe quick fix,matched with correct amp/watt extension cord and timer. please post if you have used these items to heat you vehicle for easier starting! Thank you!