FRESH AIR BOX PASSENGER SIDE

I've had good luck freeing up the hinges by soaking them in rust remover.
Distilled white vinegar, lemon juice and a sprinkle of salt:)
I bought a drivers side and made an adapter to bolt it to the pass side, can`t tell its not factory, except they both open the same way. don`t know about factory ones tho. small hotrod heater in the center - under the dash.