Convertibles and coupes were essentially the same beneath the skin with the exception of two additional body mount provisions for the convertibles. The extra two hold down bolts were intended to partially compensate for the loss of rigidity that resulted when the coupe’s roof was eliminated.
  Corvette’s interior, like its exterior, changed dramatically in 1963. Though a stretched design that could accommodate four passengers was seriously considered it was rejected as too disruptive to the car’s design and too expensive to justify given the number of projected sales. Thus the same basic design theme seen since the beginning in 1953 remained, with a two-passenger cabin featuring bucket seats, a cluster of instruments in front of the driver, and a central vertical area with additional instrumentation, heater controls and a radio on cars so equipped. But despite the similar overall architecture every detail in the new Corvette was revised and virtually no interior parts interchanged between 1963s and earlier cars.
  A consistent motif found throughout the totally revised ’63 interior was the reference to aircraft design. This is not surprising when you consider that the late 1950s and early 1960s were dominated by the rise of the jet age and by a frenzied acceleration of the race to reach outer space.
  As with the exterior and interior, Corvette chassis design was radically transformed in 1963. A ladder type frame with fully boxed side rails replaced the 1953-62 design, which relied on a central I-beam X member for much of its strength. The new configuration was both lighter and stronger than the one it replaced.