[Mark IV]

Pete Brock was influenced by the aero theory work of Dr. Kamm (i.e. "Kammback") that held a long taper was not needed and that cutting the taper off with a flat tail kept most of the benefits of the long taper. Several other designers came to similar results, the Maser, the Ferrari "breadvan", the Alfa, etc. All of those designers were heading for the same results so many of the shapes were similar.