The Death Car

Maybe somebody has explained this one, but if so I must have missed it.

As we know, he movie departs from actual events in the way Bonnie and Clyde are ambushed and killed. In the movie, Clyde gets out of the car and is shot outside, leaving the door open, at which point Bonnie is killed in a hail of gunfire through the open door. In reality of course, Clyde never opened the door, and both were hit with bullets fired through the door and open window. We can see evidence of the many bullets which passed through the drivers side door and exited on the passenger side on the real “death car” and in photos taken at the time.

The question here is how did the movie “death car” get bullet holes in the drivers door, when neither squibs nor other methods of producing bullet hole effects would have been applied to that door, which was left in an open position during the shooting sequence? The prop car, displayed for many years after the movie was made, clearly has real bullet holes in that door. Did they go back and shoot holes in it to make it more closely resemble the real death car (and therefore not represent how the car was used in the movie) or was there possibly a different version of this sequence shot but never used, which would explain the condition for the left side of the prop car?
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