Using some leftover wood from the construction of the Upper Level I was able to build quite a nice locomotive shelf. It can only fit diesels and smaller RailKing steamers but that works for me! There is space to add another shelf or two to the bottom but I may just continue to leave it open so nobody kicks anything. Right now it is acting as a home to all of my Nickel Plate Road diesels.
Dimensions are 49 x 25 inches