oh, that coal mine !!
The first time I saw that coal mine, was in a three part scratch building article by Jack Work, that started in October 1959, in Model Railroader. I built it in HO scale, out of Balsa, and about two years later,blew it up with a small fire cracker.
This was a kit in HO some years ago, and I'm happy to see it again in kit form.
The article ran october, November, and I believe either Dec.'59, or Jan '60. If you have access to MRs that old you might be interested in how it was built.
Pete