Again, the 'Masoretic text' DOES include the books of Ecclesiastes (Kohelet), Song of Solomon (Shir HaShirim), and Esther.
You are correct about these three books. However, I stand by my earlier claim that the KJV uses the Septuagint (LXX) instead of the Masoretic Text (MT) for the an important prophesies of Christ, including:
Isaiah 7:14
(LXX)-Behold, a virgin will conceive...
(MT)-Behold, a young woman will conceive...
(KJV)-Behold, a virgin will conceive...