Here are the photos of the re-creation by the secret service of the motorcade route and the view through the scope on the rifle Oswald was supposed to have used.

If he shot Kennedy, he took the worst possible shot.

He had at least three EASY kill shots as the limo came towards him and slowed to take the corner.....two of those shots were easy without a scope.

http://www.maryferrell.org/wiki/index.php/...

Check out "Scope 4 Scope 5 and Scope 6"

As way of expertise on the subject, I give you a couple photos of the very tower where I spent my tour in Vietnam. It is almost 40 feet tall.







Oswald was 20 0r 30 feet above that. The distance through the scope of the places where Kennedy was actually hit were extremely difficult shots, particularly on a moving target. And after the first shot, an accelerating target.