Denny12348 means how you manage to make the whole bodyshell in one color, because he has issues that some parts (front, roof climate, etc.) are in a darker colour, regardless if it is all Painted in the same one.
To be honest I didn't do anything special. The main body was composed out of several objects with different textures, I just detached them by material and assigned an envmap to the body which is controlled by an envmap mask (in order not to have reflections on plastic parts and rubber seals, and to have different level of reflections on windows)