I am very impressed by the amount of lighthouse research and putting-together you've done to confirm the exteriors and the interior.

Thank you. It helped that the Hartland Point Lighthouse had a uniquely distinctive lantern. Powell did claim to have used it for the North Stack Light, but he also claimed to have used other, unspecified lighthouses in his picture, and the amount of screen time devoted to its lantern room made the nature of his claim easy to double-check.