Ben - Just below the tool box is an allen bolt that holds the brake line on the inside of the frame. Use that to secure the tool box bracket that you will have to fabricate. I used an old Craftsman box that was new and never used,it is much heavier than the new ones and did not have any logo stamped into the lid.
I did post a couple more pics with the 1920's station as the background. It is a work of art, the entire building is painted wood not vinyl siding. I do appreciate the owner letting me use his stations as backgrounds
Tommy