Do you know that Bachmann makes a 2-8-0 narrow gauge Spectrum steam engine decorated for the Deadwood Central?
Bachmann's catalog number for this locomotive is 81295, and it is 1:20.3 scale.
Your rise of 4 feet in 90 is 4.4 percent. I don't know about a diesel engine, but I don't think a Bachmann steamer could pull that steep a grade with the number of cars you want to pull because the wheels would begin to slip.
Remember: In South Carolina, North is southeast of Due West... HIOAg /Bill
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