This 1999 Porsche 911 Carrera 4 cabriolet is powered by a supercharged 3.4-liter M96 flat-six that drives all four wheels through a six-speed manual transaxle and is finished in black over black leather. Equipment includes a black soft top, a TechArt widebody aero package and 18" multi-piece wheels, adjustable coilover suspension, power-adjustable…