I had a 55 1st panel with factory heat/defrost. I can tell you from experience that it SUCKED! If the weather was cold I had to let the truck run for 20 minutes with the fan on high to clear the windshield and heat the cab. The cab would never get warm if I didn't do that. If you had a factory heater it wouldn't be much better than what you have now. Good Luck!!

Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.