Rick: The Kato Mikado chassis is too long for the Spectrum 2-8-0 locomotive shell. You'll be better off with a smaller chassis such as a Kato Japanese 2-8-0 or the Micro-Ace 2-8-0. The position of the motor is the only problem with those Japanese steamers, but the Spectrum frame can be adjusted to accommodate those chassis'. Have fun with it.... Shades
The Kato Japanese 2-8-0 has the motor in the tender. The Micro Ace has the motor in the locomotive. Both are 1:150 scale and diminutive compared with the Bachmann 2-8-0. Also the drivers are smaller. Can be done but the result may or may not be aesthetically pleasing. Finding any that are available could be a problem. I like my initial response better, send them to me.