As I described a few weeks ago: I bought a CD-ROM with all Toyota Carina FR workshop books (scanned) on it and it is a treasure of information. From now and then there are a few hidden gems in there, like the initial design sketches for the four door sedan of the Toyota Carina A60:
The front is a bit more slanted than the production version and if you squint your eyes you can see the Toyota Corona A140 in it that shared the same platform. Wheel arches are more squared off than the Carina and this is quite similar to the Corona as well.
However the sketch from the rear is unmistakeably the four door Toyota Carina A60 sedan:
The tail lights are clearly the same design as the tail lights of the zenki sedan. Even the rear door has the blacked out triangular part that finishes of the lines of the rear door.
Perhaps Toyota made a study to see if they could fully merge the Corona and Carina with the A60/T140 generation? Eventually they managed to do it in the next T150 generation.