Hi Dean, The older Stewarts are what I have. I'm re-entering the hobby after years of things being in storage while I moved around for my career. I'm retired now. All of my Stewart F7 and F3 fleet is original Stewart/Kato. It all runs great but is purely DC. I've collected trains for 50 years and never had a serious layout but am building one now. I am wiring for DC and Railpro because it isn't practical to convert everything but my favorites are the Kato, Stewart, Atlas and a couple of Proto 2000 types. Any info or photos you could provide would be appreciated. Mostly you've answered the most important question I had which is will it fit into the Stewart F7.