http://www.flickr.com/photos/14696209@N02/3724312218/
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Ffarm3.static.flickr.com%2F2517%2F3724312218_1e7e778b42_o.jpg&hash=a209c9c4f43f9be781a7f8a0b11e855dddfbf73b)
Looks to be white-on-black signage at today's Exit 433C (9th Street from northbound US 101 where it transitions from the Bayshore Freeway to the Central Freeway) with no shield for the pull-through. This was probably when the Skyway was finished as US 40 and US 50, before I-80 was signed in the late 1950s/early 1960s.
And yes, the Coca-Cola sign in the background is still there!
http://sphotos.ak.fbcdn.net/hphotos-ak-snc4/hs164.snc4/37521_935333107823_3216777_50385736_6905496_n.jpg