I was at a local car show and saw an 84 Firebird that had speakers in the door. It looked like an enclosure of some kind that added depth to the door and matched the interior. Anyone seen one of these. The owner said he picked it up at a swap meet and thought it was a factory option at one time. I did a search an got nothing back so thought I'd see if anyone else had seen something like it.
1991 Z28 5.0 Standard
1995 Camaro 3.4 Auto
I'm not sure about the 3rd Gen firebirds, but the Camaros didn't have door speakers from the factory. They have 4x6's on the dash and 6x9's in the rear seat side panels (sail panels ). Any other location would be custom.