Thanks! So it looks like SP went up what's now the Great Highway south of Golden Gate Park and what later became the streetcar r/w across the west end of the park onto La Playa, with a terminal near BalBoa St., then back through the park and in on Lincoln Way to a terminal near Stanyan St. Interesting. In later years (the 1915 maps, for instance), there definitely were streetcars crossing the park on that alignment, mostly grade-separated.

I have a random collection of WR's but don't remember seeing one with discussion of that service. Obviously, one I don't have.