AC Box Rebuild-Missing Flapper Door

Oh, ok. Maybe that blower switch goes in a different location on a 1967 vs a 1971? Or maybe it didn’t one at all in ‘71?

Not even sure if I’d really need it? I’m thinking that it turn the fan on high when the actuator moves one way or the other?
I have to look at the parts that came off and get back to you. Is there something else missing?