Thanx for posting the youtube link GW
. the tunnel that Audrey Totter is contemplating 'cide of the sui kind, is the hill street P&E tunnel at 1st street
Source:
LAPL http://jpg3.lapl.org/pics37/00068279.jpg
which as we know is long gone
Source:
LAPL http://jpg3.lapl.org/pics37/00068280.jpg
(amazing that these two images are of the same view)........
the scary thing about the scene from the film, is how fast the red cars are travelling on hill street....at grade.....while co-mingling with street traffic....wow! those trolly's look like their doing 35 mph or better