Wilson Pickett caught the mood of the nation when, in his blues song, Mustang Sally, he sang "I bought you a brand new Mustang 'bout nineteen sixty-five." Sally's was only one of the 680,000 Mustangs that were sold in 1964-65 as the car that Lee Iococca and his committee of eight designed wildly exceeded sales projections.
The Mustang was introduced in March of 1964 and those built up to August of that year are often referred to as "'64½s" although that was not an official factory designation. Adding to the naming confusion, Mustangs built before August 17th, 1964, equipped with generators and a GEN warning light, are often referred to as "early '65s." Those built after August 17th, alternator-equipped and with an ALT warning light, are called "late '65s." Engines in the late '65s are more powerful; the 200 ci six-cylinder picked up nineteen horsepower (120 hp) and the 2-barrel and 4-barrel versions of the 289 cubic inch V8s were boosted to 200 and 225 horsepower.
The tire-burner's delight was the high-performance K-code 289 ci, 271 hp engine, a $276 option, introduced in June of 1964 and only available with a four-speed manual transmission. The coveted "Pony" interior-indicated by a "B" on the body code stamping on the warranty plate-included embossed ponies on the seats and a five-instrument dash. Introduced in March of 1965, the codes and introduction dates are significant since there is a dramatic diminution in value if a Pony interior is a recent, aftermarket addition rather than original.
The most desirable 1965 Mustang convertibles are the Indianapolis 500 Pace Cars used in the 1964 race. Two were used for the actual race and thirty-five others were given to race dignitaries. Painted Pace Car White, and equipped with a 260 cubic inch V8 and automatic transmission, they rarely come up for sale and don't fit the definition of affordable when they do.
The ideal Mustang convertible, in terms of current market value, would have the K-code engine, air conditioning, Pony interior and the GT Equipment Group which consists of the Special Handling Package, rocker panel stripes, manual front disc brakes, grille-mounted fog lamps, chrome exhaust trumpets and GT emblems. (These options would have added about a thousand dollars to the $2,557 base price in 1965). Today, this car, in excellent condition, would be worth more than $30,000. However, finding an original vehicle will be difficult since the numbers work against us. Only 5,300 of the 99,000 1965 convertibles were ordered with the Pony interior, only 7,200 of all the 681,000 Mustangs had the K-code engine and 15,000 had the GT Equipment Group. The subset containing all three options is rare indeed.
However, a non-K-code, non-pony, rust-free convertible with a 260/289 and an extensive list of options, even if added aftermarket, will provide a ride with a lot of eye appeal, more than adequate performance for every day driving, acceptable appreciation and best of all, reliable transportation with a readily available parts supply.
All Mustang parts have a date code that is either stamped or cast into the part and the date could be as much as thirty days prior to the actual build date. Make sure that the codes on the door and fender plates match. There are a host of Mustangs originally built as six-cylinder cars that now sport V8 engines. Shun them unless they are offered at a 50% discount from normal market. Check for rust and if you must have a six-cylinder, avoid the manual transmission unless you want to be on a first-name basis with the transmission shop.