Youtube provides plenty of evidence that anyone with a napkin sketch, a TIG welder, and some 4130 chrome-moly tubing can make a car chassis. Building an engine to power that chassis is another matter. Napkin sketches don’t cut it when tolerances are measured to the zillionth. You also need a rail line to bring you a steady supply of iron ore, plus a blast furnace, a foundry, and heaps of casting sand. And a whole wardrobe of fireproof clothing. Overhead, in other words. What’s a low-volume car manufacturer to do?
This is a companion discussion topic for the original entry at https://www.hagerty.com/articles-videos/articles/2018/06/06/european-design-made-them-pretty-detroit-v8s-made-them-fast