The fastback was added to the 1965 Mustang lineup, although the coupe continued to be the best seller of the group. For some strange reason, the coupe outsold the convertible and fastback five to one, accounting for nearly 75 percent of total sales. This is hard for me to believe because in my opinion the fastback is such a cooler looking vehicle.
In April 1965, the first Mustang GT was introduced. They were available in all three body styles (coupe, convertible, and fastback).
Two optional V-8 engines were offered to the public with the GT with either 225 or 271 horsepower and a choice of a three- or four-speed manual, or a Cruise-O-Matic transmission. The 65 GT Mustang also included a different dashboard instrument cluster that became standard in 1966 mustang models. The GT had awesome stripes on the lower body sides, dual exhaust tips, fog lamps in the grille, and GT badges on the front fenders. To upgrade to a GT you had to cough up an additional $165.03. This was a lot back in 1965, but by today's standards, you almost want to kick yourself in the foot for not upgrading.
There was also an interior upgrade available for 1965 and 1966 Mustangs. The Deluxe or better known "Pony" Interior included two-tone seats with running horses stamped on the backs.
Shelby Mustangs were introduced in 1965. They were all fastbacks with no rear seat and the spare tire mounted under the rear windshield. I am not sure how much of a difference removing these items lightened up the car, but it definitely made it sporty looking. The 289 engine was pumped up to 306 horsepower. They were all Wimbledon White fastbacks with black interior and Guardsman Blue stripes. The fuel door wore the pony & tribar Mustang emblem.
1964's "Goldfinger" was the first major motion picture to show a Ford Mustang. James Bond drove an Aston Martin DB5 while chasing Tilly Masterson in a white 1964 1/2 Mustang convertible. Bond's center caps popped out and became spinning blades, which slashed the Mustang's tires and destroyed the body panels. What a shame!