Early VAIs and VAOs had the wide, non-adj. front axles. The VACs had the option of single, dual, wide (non-adj.) or wide adjustable front axle configuration. Without the plate it would be virtually impossible to tell an early flat-floor VAO from a VAC fitted with the wide, non-adj. axle. The only clue would be the rear axle length as the VAO used short axles while the VAC COULD be ordered with various lengths. BUT a VAO MIGHT have been ordered with them from the factory or had some installed later. In addition; the early VAO was flat-floored and then the dropped floor model became available. The drop-floor models had issues with pedal/pitman arm interference in a left turn as well as foot clearance on the brake side with the optional control valve which was used with the early live hydraulic system.
An early flat-floor VAO is shown (note: the rear axles have been bobbed with a torch and later hydraulics added). Click the link for more info.