Caltrans' Postmile Query Tool has CA 47's west end at Gaffey St., about 0.14 mile west of I-110 where we now have the west endpoint.
That extension consists of a one-way (WB) ramp, which is how WB CA 47 traffic would connect to Gaffey St. south beyond I-110's south end into San Pedro, which used to be part of route 110. There is no ramp from CA 47 directly to I-110 SB. The corresponding ramp to EB CA 47 from San Pedro is from NB I-110 just after its intersection with Gaffey St. The extra mileage only for WB CA 47 traffic bothers me, though I'm not sure it should.
I'm tempted to go no-build on this, except two exit number corrections needed for the part of CA 47 already in the HB. Any thoughts?