This is 5R002, the Shelby GT350 R Model prototype, the very first one (it was built before 5R001 which was the second and hasn't been seen public since the 1980s). Its known as the "Flying Mustang" that was in that famous photo. It was driven and tested by Ken Miles (British driver that moved to the USA) and 35 more were made. The 1965 Shelby GT350 R Models won the SCCA B Production Championship 3 years in a row (1965-1967), Ford tried the Tunnel Ram V8 in 1968 and then in 1969-1970 the Boss 302 Mustangs (in 1971 a Boss 351 street version was made). Also this car shortly later within 2 hours of 3.7 Million USD and after taxes came to 4,070,000 USD at the 2022 Mecum Kissimmee Auction.