The fatal shot came from the front right side.This is clear from Kennedy's recoil to the back and left. If Jackie had shot him from his left the recoil would have been to his right. As I recall the first shot hit him in the throat. She was clearly trying to assist him when the second shot came from the front right and hit him in the head. She panicked and climbed over the seat to where the secret service agent should have been stationed on the back of the car, but wasn't.