Thanks for the replies. Admittedly, I hadn't thought about having a guy
inside the boiler, but I suppose that's possible if he enters through the steam dome. Would get kinda tight as the boiler shell fills with tubes. I suppose that "fishing" from the firebox end would be workable as well. What got me thinking about the question was wondering how it's getting done in Chama on #487 right now. Would expect that it's a whole different ball game than working on the Forneys in Maine!
Ed Frey
Loveland, CO