Here is a couple of more photos I found. I think the white impala mirror is aftermarket however.

If I recall correctly I have seen them in two different spots, on the door and also mounted on the fenders. I have also seen mirrors mounted on the door/window frames (front upper portion) but I believe these were an aftermarket clamp on type mirror. Most cars of that year didnt have mirrors, it was an option which many didnt spring for.