1986F150Six wrote
Thanks for the clarification!
For what it's worth, they're easy to tell apart because the 87+ trucks have plastic doors in the A/C box, and the levers that control them are plastic as well.
I prefer the metal versions because although they rust and the foam comes off, the box that came from my F350 once housed a rat that chewed through one of the plastic doors. Luckily, I was already planning on going with the 86 box from my parts truck so it wasn't a huge loss.