Ford offically introduces Mustang on April 17, at the New York World's Fair; 100,000 are sold in four months. A Mustang convertible paces the Indianapolis 500. The Mustang Fastback bows on October 1; a 200-cid six is standard. After September, Mustangs 260 is dropped in favor of the 289.

The Mustang-based Shelby GT-350 Cobra officially debuts at Riverside Raceway on January 27. A competition version of the Shelby GT-350 Cobra, the GT-350R, is homologated for SCCA B-production. 2+2 Mustangs fitted with Ford's 427-cid big block regularly win NHRA/FX-class races and, occasionally, "funny car" competitions. Total "1964.1/2" - 65 Mustang model - year sales are 680,989; convertibles account for 101,945.

Alterations to 66 Mustangs are minor, and include revised standard hubcaps, grille, and fake side vents. Styling studies toy with the idea of a "Kammaback" Mustang station wagon badged Aspenl; a targa-top convertible is also considered. Mustang sales for 1966 dip slightly to 607,568, and includes 72,119 convertibles; with 7.1% of the total market share. Mustang becomes the industries third best-selling nameplate.

A 390-cid "Thunderbird Special" V8 is now optional with Mustang. An all-new dash helps Mustang shed a remmnant of its Falcon origins. Carroll Shelby drops Ford's 428 into his Shelby Cobra and creates the GT-500; advertised bhp is 335 but is probably more; a 390-bhp version is a seldom-ordered GT-500 option. With 472,121 model-year sales, Mustang outsells Camaro by a two to one margin; 44,808 of those Mustangs are convertibles.

Ford assumes control of the Shelby-Mustangs, moving the production from L.A. to Michigan. Mid-year brings the Shelby Cobra GT-500KR (King of the Road) with 428 Cobra-Jet V8. Model-year Mustang sales are 317,404 and include 25,376 convertibles; respectable but a dramatic frop from 1967.

The Boss 302 (approximately 400bhp) arrives early in 69. The Boss 429 competition engine is made available to Mustang buyers for homologation purposes. Shelby Mustangs are now built at Ford's Southfield, Michigan Plant alongside stoch Mustangs. Mustang Model-year sales is 299,824, including 14,746 convertibles.

Lee Iacocca is named president of the Ford Motor Company. The top Mach I engine for the year, the 428, is replaced by the 429 during the model run. Mustang, sans Shelby participation, comes out on top in the Trans Am race season. Model-year Mustang production falls to 190,727, including just 7673 convertibles.

The redesigned Mustang gains 600 pounds and eight inches in overall length, though wheelbase grows only by an inch. Mustangs top engine is a new four-barrel Cobra Jet rated at 370bhp. Total model-year Mustang Sales drop further to 149,678; 6121 of those were convertibles.

Mustang styling continues much the same as 1971; Sprint Decor option - comprised of lively fabric, colors, and wheels -- is introduced to try and increase sales. Model-year Mustang sales amount to 125,093, including 6401 convertibles.

Mustang is the only Ford product to offer the division's High Output 351 V8. Ford announces that "1973 will bring the final Mustang convertibles". Mustang Model-year sales rebound slightly to 134,267; with convertibles sales almost doubling to 11,853.