How would I go about building a SW12 or B23-7 in G? I would like both but nobody makes them comercially that I know of. Where to start....
Well my suggestion would be since you seem like a begginer is to buy a commercial made train that closly resembles this unit. Then see if you can get prototype photos with dimensions and then start to modify the model you bought. Like maybe the Aristocraft U25B would be a good model to modify to your application