There’s quite a lot different in these next photos. I was just using the same techniques so I thought it would be better to not explain each and every little part I modelled. Although I did change some of my existing geometry to make some of the lines look better.
So I extended the rear even further past the arch to the back. I used the same wheel arch from the front but modified he geometry to match the shape of the rear. I also made the front splitter. I may change this for a different more aggressive looking splitter though as the stock one doesn't look that great.