Revealing mistake: When Kimble leaps from the truck and runs into the woods, the stunt double's face is visible. (00:07:00)
Visible crew/equipment: Gerard drives away in his '64 Ford Galaxie, and the side of the shiny new car captures a clear reflection of several studio lights and reflectors. (00:10:10)
Answer: Production vehicle models aren't in sync with the calendar year. The '65 Mustang began production in March 1964 and first sold in April 1964, before it was "introduced" the following year. I don't know which model was seen in the episode, but the 2+2 fastback was sold in September 1964. The 1964 film "Goldfinger" uses a 1965 Mustang as part of Ford's product placement. Basically, in the 1930's, FDR ordered automakers to release vehicles in the fall of the preceding calendar year "as a means of facilitating regularization of employment in the industry." Now, automakers can release new models as early as Jan 2 of the preceding year.
Bishop73