Complex sentence: The Rev. W Awdry wanted the story to be as close to what really happened as much as possible, but did not want to distress the readers so he added that he had made up the story.
Split into simpler sentences: The Rev. W Awdry wanted the story to be as close to what really happened as much as possible. But he did not want to distress the readers so he added that he had made up the story.