Thanks for the info and replies.
Franco, as far as a steel boiler not lasting long when running steam, I disagree. I personally know of a 1929 Titusville series W Tico coal boiler was in outstanding material condition when they cut her up. Throughout the years running on steam, it only lost from .005 to .010" of thickness from from the original design. I believe it started out at .720 and at the end of it's life was .710 to .715 after 77 years of service. Good water treatment and care goes a long way for the life of any boiler. I know of 97 year old steam boilers that are still in operation, and again are in outstanding condition. Of course these have been well maintained. For further evidence you can look to many of the steam locomotives that are still in operation as well. Some of course require overhauls and so on, but they are a testament to the outstanding standards of that time. As for my boilers, I treat the water always.
Steve, in regards to switching from steam to hot water, I really would like the boiler to be in the exterior utility room. Radiator height inside the house is an issue for the boiler to be located in the exterior utility room as some of the radiators are below the boiler NOWL. This would cause them to fill with water, be ineffective and probably result a flooded system. I believe there is room to raise the radiators above the water level of the boiler. The other issue would be the header. The exterior utility room, for steam would require the main steam pipe to go out and across at a height of about 7' or so and a length of about 12', then down and across a few more feet into the main steam header. Of course this would all be insulated. The return would travel under ground to the boiler in the exterior utility room. I would run heat trace along the return line, insulate it, and also put a remote temperature sensor on the line in order for the heat trace to turn on at a set temperature. Other ideas would be a condensate return tank with one active pump and one backup. The float system would pose a problem, as the boiler would probably require make up water, and that additional water in the system will eventually flood it after a few cycles. That would require expelling the condensate from the system, and would be a waste.
The current steam boiler is located in the basement. I for one do not like the steam header and wonder why it is they piped it this way. I would change it to a nice dropped header, but I do not wish to waste any more money on the system.
As for my Axeman Anderson, it was built in 1953.