SP interchanged with WP at the WP yard by Illinois and Army Street. That somewhat changed when the WP ferry was taken out of service. WP freight came around the Bay on SP (picked up at Fremont-Shinn, usually by East Pleasanton Turn), to Bayshore, then (I'm trying to remember in the middle of the night!) to 14th Avenue (opposite Quint Street) where WP picked up to their yard. Funny thing was WP had scrap customers in South San Francisco and you guessed it!, SP would pick up those cars at Army Street, back down Illinois Street, to the interchange by ATSF yard, to Mission Bay, back to Bayshore, to South San Francisco. What a cost accounting nightmare, involving one SP local, up to four SP yard jobs and maybe 2 WP jobs. I don't know when that ended.