I have a 76 F250 Crewcab with a 390 4 speed that doesn't have ac or any of the ac vents. It also has a bad heater core. I also have a 78 F350 Supercab with a 460 auto that has ac with all the vents. I'm debating on whether or not to switch the ac to the 76? It doesn't get to hot here very often. I'm selling the Supercab.