now had featured a new second-row seat mechanism folding it down and forward to offer of flat-floored cargo space with the tailgate opening also made wider and taller than the 1966 versions. The Rebel models were similar to the senior Ambassador in that they shared the same basic unit-body (platform) aft of the cowl. Rebels came in the base 550 and deluxe 770 models, with a high-line SST available only as a two-door hardtop. Traditional Rambler economy came standard with the redesigned Rebels featuring six-cylinder engines and overdrive transmissions. However, the Rebels were upgraded in numerous areas including a new four-link, trailing-arm rear suspension system. American Motors also introduced advanced V8 engines, and Rebels could now be turned "into a decent budget-priced muscle car" with the new . Moreover, American Motors expanded its racing activities in 1967 by partnering with automotive performance parts company, Grant Industries, to build the Grant Rambler Rebel, a "Funny Car" racer to compete in the National Hot Rod Association (NHRA) X/S (Experimental Stock) and Super Experimental Stock classes. The relationship provided both companies with national exposure and publicity. The racing Rebel had an altered wheelbase with chrome moly steel tube chassis and powered by the AMC V8 engine that was bored and stroked to . The engine featured a GMC 6-71 blower and Enderle fuel injection, producing at up to 9000 rpm on a mixture of alcohol and nitromethane. In 1967, Hayden Proffitt drove the Rebel on the quarter-mile (402 m) from a standing start in 8.11 seconds at . 1968 For the 1968 model year, the historic "Rambler" marque was dropped and the line was named AMC Rebel. The cars received only a modest restyle, but incorporated new safety features mandated by the U.S. National Highway Traffic Safety Administration (NHTSA), engine control systems to reduce unburned hydrocarbon and carbon monoxide emissions, and the availability of the "AMX" V8 engine. Declining sales of convertibles in general during the late 1960s saw discontinuance of this body style by AMC after only 823 were built in 1968. Production of Rebels continued through the 1970 model year until replaced by the similar AMC Matador for the 1971 model year. Production Fifth generation Rebels were built at AMC's main assembly plant in Kenosha, Wisconsin and in its Canadian Brampton Assembly in Brampton, Ontario. Foreign assembly from Semi Knock Down (SKD) kits was undertaken by Australian Motor Industries in Australia