I think they were built by Dorsey. We had some blue B&M ones rotting away at Iron Horse Park in N Billerica, MA until fairly recently. Mont Switzer wrote an article on how to build one like that from an Athearn Freuhauf Z-van in Mainline Modeler. REA Leasing was a big owner, solid red paint, leased to various roads.

Mike Clements
Wakefield, MA
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