Please clarify best way to add smoke fluid to the whistle steam smoke generator on Lionel Legacy N&W J Class Steam engine. The Owner's Manual states on page 8 to "remove the fill detail piece". I have never done this before, and do not want to accidentally break anything. What is the correct way to remove the fill detail piece? (This is brand new out of the box J 611, with corrected paint. Awesome gorgeous (and expensive).)
Thanks!