Well, this "grassy slope" is getting crowed. This is the Same "grassy slope" that Umbrella Man/Witt claimed he was walking down while fighting to open his umbrella.
If Woodward did Not Know where she was standing, how can we believe she Knows what she is claiming to have seen? Just put yourself in the jury box. Of course, I'll be the Foreman.
A big "if". Not only did Woodward know where she was standing, she described it in detail in her FBI statement: "They walked to Elm Street and stopped in front of the Texas School Book Depository building, but were located a short distance down the street near the second light post. There were standing in this spot when the Presidential Motorcade came by."
She then went on to tell the FBI that they cheered loudly as the President and Mrs. Kennedy went by. "Just as President and Mrs. Kennedy went by, they turned and waved at them. Just a second or two later (ie. after JFK and Jackie turned and waved at them) she heard a loud noise."
JFK began that turn and wave at z172. A second after that is z190. Two seconds is z208.