Nothing missing. Just that on my old AC housing, the one that had the missing AC flapper door, there are two holes for that switch to bolt to the housing like in that picture.
It looks like the “lever” that the actuator attaches to, also triggers that switch when the door opens, or closes. I don’t see anything on the lever on new AC housing that would flip that switch as the actuator opens and closes that door.
I can probably fabricate something. But I was wondering if any knew exactly what that switch does and if I should even bother trying to hook it up.