Thank you, Jay, Bob, and Jeff.
Maybe I should install a smoke unit in the chimney! Oh, I almost forgot; the Fire Chief says no smoke indoors! 
Bob, you are so right! David Eisinger told me there wasn't much of a tab to hold them in place. He was right. It reminds me of the fiasco of trying to build the Walthers substation. In that case, I pulled the 'good enough' lever and bought the Woodland Scenics substation. 
Jeff, I understand what you mean about snowbirds. None had roosted in that photograph that I reused from a couple weeks ago. In Western Pennsylvania 'snowbirds' are those folks who winter in Florida. I didn't know what to call them, and David Eisinger called them snowbirds which is what Tichy calls them. I learned later that the term 'snow guard' was used on the drawing of the prototype, and a manufacturer of the 1:1 scale ones are called snow guards as well. I may go 'cuckoo' trying to install them. 
