Looking better already and thanks for following my advice. Now try to fix the rear window (as I already said, it sticks too much out). The next thing is to fill the gap between the rear wing and the rear arch (the spot near the left taillight). I find it hillarious that you´ve just put some red lines on the rear bumber to match the color
The space above it (the big plain red spot on the top of the bumper), make it match the colour of the rear wing. (CTRL + U)