I took the image of the real car and overlayed it on the scoop on your model.
These are taken at different angles, but hopefully this helps:
Looking down at the top of the rear fender, the fender shouldn't get much narrower between the wheel well and the scoop. Hopefully you can see how much I painted on the top of the fender to make the scoop fit. The faint edge of your fender can be made out, cutting through the middle of where the scoop opening needs to be.
Also, the opening of the scoop looks to be about as high as it is wide - you need to extend the opening further down, like here:
I probably went a little too far but I think you get the idea.