I just reviewed the photos Tom posted and compared them to some others I have. I believe I can actually spot the car from Tom's photo in the overhead shot from the helicopter (SEE BELOW). Indeed, that car is near the intersection of the Angled Road and the Old Gravel Road.
Additionally, the indention in the shoreline does correlate with the 1979 photo but appears to be somewhat more pronounced. I attribute this to a different water level--probably higher in the 1980 photo.