Ok, Don.
With only the one train to worry about, and only the one track, I think GGG's suggestion of modifying the engine is probably the way to go for simplicity. This would let you drive the motors at 22-24 VAC to get optimal performance out of them. I think George here may have a better understanding of which boards need what voltages, but I'll have a look if you can provide any documentation on exactly what is in these engines.
For GGG, is it only the R2lc that has problems with high voltage, or are there other components as well? I'm not familiar with the various products offered by ERR.
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As to the Arduino route, we can still play with it if you like, seems like fun.
JGL
