This was mentioned in a model magazine. I have found it easier than I thought
to find vehicles appropriate to my modeled year, but, even in HO, I have wished they would put the year the rail car was introduced on the protoype, on the box.
It is not on tinplate boxes, either, and I am sure I have cars that will not belong on my finished (if that ever happens!) model RR.
Was this a monthly or a yearly (sounded monthly in the article) publication,
and for what years does it exist? How useful would one really be for that task
of identifying tinplate cars that are appropriate for a period?