Help, need cable operated vent assembly . Non Mopar application

[Brads70]

Ok I need to pick your collective brains . Working on installing a Vintage air A/C set up in my Javelin.  What I need some idea's on is plugging the cowl air opening as Vintage air doesn't use it. I'd like something that I can pull a cable and still have fresh air blowing in when I don't need the A/C . Something as flat/compact as possible would be nice? Say 6x6 or so?  Any idea's? Or any idea what car application I can source something from?  I can just make a plug thats easy but would like something with a cable operated door so I can use it still if need be?
More or less a cable operated blast gate ?

[RUNCHARGER]

Hmm: Can't think of anything off hand. I bet some kind of a 60's pickup or large truck would have something like that. I'm thinking International with a vent in the side of the cowl maybe.

[anlauto]

Just get one of these 6"W X 6"H ADJUSTABLE AIR SUPPLY DIFFUSER  and hook a cable to it !  (even comes with screws)

...now that's "outside the box thinking"....