It’s maddening that the first bullet hits Kennedy just as a large highway sign comes between Zapruder and the president.
Frame 224 also proves there was a single bullet that went through Kennedy's neck and hit Connolly because you can not only see Connolly's position in the car (turned to the right), but his reaction to being hit and his collar flipping out as the bullet passes through him and hitting the collar.
It's all there.