Arizona Railway Museum Image Database Santa Fe GP35, #3407, at the Mobest roundhouse. General Motors Train of Tomorrow demonstrator at Phoenix, AZ in May 1948. SP #2161 at Phoenix roundhouse in December 1947. SP #2601 near 18th Street in Phoenix, AZ in December 1947. SP #4305 at Tucson, AZ in December 1947. SP #4432 at Tucson in December 1947.