I suppose a auto smart person could take a basic car and rebuild it to his satisfaction from parts manufactured by car makers….
Take the Kyushu Danji NSX for example – a machine that only shows up at Tsukuba Circuit a couple of times a year as its owner lives at the opposite end of the country. The first time I came across the Honda was back in February 2011 when it largely still resembled a street-tuned car. It already had widened bodywork, but not anywhere as extreme as the GT500-inspired aero outfit it wears these days. Of course, everything you see around the car and underneath it too is brutally functional.