In the final chase, the right-hand mirror on the delivery truck gets shot out. In later scenes, the mirror is intact.
Cases of bottles fall out of the rear of the truck during the final chase. After the chase, when the delivery truck stops, the cases are still stacked up in the truck.
When Harley's air boat runs across the road and is nearly hit by the Buick Skylark, the car stops at a slight angle on the road. When the second air boat follows him, the Buick is now at a much more pronounced angle to the road, even having the rear tire off the pavement.
Many of the stunt drivers during the chase scenes are visible, who look absolutely nothing like the actors.
When the delivery truck and the Buick wagon take off from the Flight Path Cafe, the shadow of the camera chopper is visible.