Dave,
Any markings that would show a return trip to the factory?
Or lack of markings? I ask this, as the rib has no marks at all. This may be the norm, but I haven't looked at a 1900 in a long time and my image searches didn't turn up much.
Bores and Chokes:
Rt: .733" - .003"
Lt: .730: - .015"
Appears someone may have wanted a bit more than CYL in the right barrel. Bores are bright and shiny and the exterior is a very nice black & white.
All metal was very dry. Pulled the stock and forend and a coat of oil and some bronze wool really made a difference. Was concerned about the bores as they were very, very dirty, but a single pass with a bore snake brought out the shine.
Had clearly been stored for a long, long time. The other four guns from the same estate were the same condition.