A design flaw set the transition between the flue section of the boiler to the firebox section set it up about 3 inches higher than the original boiler which made it unsuitable for an 1875 restoration. All the mounting points on the boiler perfectly fit NCNG #5/Tahoe so no issues there. The mud ring was also set up about 4 inches higher which required making some adjustments to the lower mounting brackets. This shorter firebox space was made up with a deeper firepan which is not noticeable unless you are looking for it. We also had to add additional steam ports plus a manifold connected to the steam dome to support all the additional appliances that had been added since 1875.