Thanks for the responses. I will have to see if I can find my old NTrak steam loco book. I went on site and see there are Annuals, addendums and updates which I never purchased. downloaded the index and there seems to be lots of no specific update of the original table. I see that some can do just about anything to build a mechanism to get close or exactly what they want. I am not near that level. So was thinking of going the other way. Looking for x-6-x with odd wheel spacing. Kato Japanese C11 2-6-4 has the odd spacing. Could it work?