Well, the CMO can speak to that better than I can, but the short answer is that much of the work you see was done in order to meet current boiler certification requirements. The boiler was removed from the frame, and shipped out to Seattle Boiler Works where it recieved extensive testing and repairs as needed to replace areas that weren't up to spec. Obviously all their work meets current regs.
All of the work was done by a professional boiler shop (SBW) and the FRA was involved in the entire process as well.
You'll find lots of details and more photos of the project here: [
www.mrsr.info]