I believe that the last operation of #9 was in August of 1959.
At the end of August 1959 my family visited the railroad while on a vacation trip (I was 10 years old and already well into railroads). The photos we took at Owenyo, Laws and Keeler carry dates of August 27, 28 and 31, 1959. Some place around here I have the file folder my mom gave me with the correspondence she had with the SP agent at Owenyo before we made the trip.
I recall that the reply gave a period of time that the 4-6-0 was to be used while the GE diesel went to Bakersfield for servicing. That time period was about a couple of weeks before our trip.
Brian Norden