Well, Branchline put the paint scheme date on the box.
Rapido, True Line, Tangent, Exactrail, and Intermountain (and probably some I’m missing) have various amounts of information on their website and packaging, and we at Prototype Junction have specifically stated that we will put a reweigh date within 6 months of the earliest documented application of a paint scheme.
MTH specifically labels cars that are fantasy schemes.
So I think this is/has been done to various degrees already.
I can’t speak for other manufacturers, but I’m sure the majority are happy to answer questions when asked.
But if there are things you want us to put on the label at Prototype Junction, let us know. Of course, it will have to wait until we relaunch, but we are happy to provide any information that will make it easier for the modeler you choose which of our models they would like.
I doubt we are unique in that regard, but message received. More information on the labels/website.
Modeling the New Haven Railroad 1946-1954