Prized Porsches from comedian Jerry Seinfeld’s collection are coming out of the vault and will be available at Gooding & Company’s Amelia Island Auction in Florida on March 11.  Seinfeld is giving up stewardship on 16 examples from his extensive fleet, including: a 1955 Porsche 550 Spyder estimated to be worth up to $6 million; a 1958 Porsche 356 A 1500 GS/GT Carrera Speedster valued at up to $2.5 million; a 1959 Porsche 718 RSK (estimate available upon request); and a 1974 Porsche 911 Carrera 3….