I can remember reading a now old photo book that talked about
a Santa Fe freight train that ran from Northen California to Los Angeles.
This train ran with a caboose on BOTH ENDS of the train for "quick reversal at Barstow".
I think the Santa Fe train symbol was "NCX" on this freight train.
I remember seeing a photo of this train on the Tehachapi Loop at Walong Siding.
This means that the ATSF did NOT have a mainline wye in Barstow prior to the 1976 "new" Barstow Yard.
That would explain why any Stockton or Bakersfield train would need a run-around move
at Barstow prior to (I think) 1976 when the giant Yard was opened in the western part of Barstow.
The old Barstow Yard was located directly across from the Harvey House on the SOUTH side of the mainline.
Here is a Google Map of Barstow, California which seems to show the OLD mainline connection.
The present-day mainline connection runs along the new Highway 58 bypass at the west end of town.
[tinyurl.com]

That is about all I know about the historic Barstow Yard facilities.
I hope someone else can add more about the pre-1976 layout of the Barstow Yards and Barstow passenger Depot!
--- Daniel