Having checked with our Technical Department, we can confirm that with regards to your enquiry, there will be no V6 engine for the new C-Class, and therefore there are no current plans for a 350CDI or 3 litre petrol engine on the new C-Class.
With regards to colours, the vehicle has only just been launched so the colour pallette is limited, but the range may be expanded in the future.
Should you have any further requirements please do not hesitate to contact us.