SP 670513-670524
These cars were origianlly built by NACC (A64B) as NADX 2664-2675 in xx/196x. They were later acquired by SP and renumbered as SP 670513-670524. A good article on the North American Car Company's line of 50' smooth side RBL's was written by Jim Kinkaid for the July 1994 issue of Mainline Modeler magazine.