[morski]

Once you have filled the area with paint and is proud of the surrounding area use 2500 followed by 3000 grit wet n dry to level it off. Then go over it again with your da and your scratch will almost disappear. this is what i do and works well.

 

[morski]

Go easy with the sanding as without a paint gauge you could end up going through the lacquer and paint and you will end up with a door that needs repainting.
Sometimes its better to quit whilst you're ahead. If you personally need to look for the damage on the panel then i doubt anyone will notice ti all.