The wattage does not matter as there is very little amperage on the circuit. I'm using 1/2 Watt resistors. This can be done in less than 5 minutes. Order a pack of the 330W k-ohm resistors. Order a pack of 22 awg d-sub contacts. On amazon, the cheapest I could find was a 200 pack of male/female contacts. I cut two pieces of 20 awg wire at about 4" long. Stripped both ends and solder a male contact on each wire. Best to use a little shrink sleeve to insulate the connections. Then solder the other ends of the wires to the wires from the resistor. Form it in a U and shove both male contacts into the rear of the connector plug that runs from the main harness that plugs into the sensor. The contacts in the factory connector kind of float, so pull on the wires slightly to create and opening to shove the contact into. You can run this way as long as it's above 75F. If the outside temps get down to around 75 or lower, you will freeze up. I had vent air blowing at 34F with 72F outside. Too cold. When it gets 75F or cooler outside, I added a toggle switch to where I can easily turn it off. I added the potentiometer to add a little more resistance for when the vent temps get below 39F.
