Objects aren't "N, HO...S, O, etc. SCALE". An object is what it measures.
That is the idea behind 55n3, we are taking models from other scales and converting them to 55n3. No one makes 55n3, Bachmann makes models that can be used in 55n3 because they match plans in Scale55. That is why we have a scale rule. Measure a model, if it is the right size for Scale55 it is Scale55. The Bachmann On30 equipment is small O scale narrow gauge, but put a Scale55 ruler on the equipment and it becomes 55n3. Now it is realistic three foot equipment.