Between 1972 and 1981 CA 99 also carried "Temporary I-5" shields as well. These were smaller (24x24) shields, generally posted on CA 99 reassurance assemblies below the CA 99 shield. From top to bottom these assemblies read: (DIRECTION)/CA 99/ (TEMPORARY)/I-5. Northbound, temporary I-5 signage began at the I-5 CA 4/Charter Way exit in Stockton, extending east on Charter Way (old US 50 and, east of the CA 4 divergence, unsigned CA 26) to CA 99, then north on CA 99 to (then) I-80 (now Biz 80 & US 50). After I-5 was completed southward into Sacramento by 1976, "temporary" signage ceased and "TO I-5" appeared on the interchange's BGS (as it does today) in order to direct traffic to the new I-5 alignment. Prior to that time, "Temporary I-5 signage followed the I-80 freeway to northbound CA 113 near Davis, which also received signage as "Temporary I-5" (this was also the routing of the former US 99W). It followed the old 99W alignment, turning west onto (then) CA 16 at Woodland and following it to a point west of town where 99W had historically turned north. It then followed the old US 99W routing, which was gradually being bypassed by I-5 construction. The entire Sacramento to Redding portion of I-5 was completed by 1976, at which time the "Temporary I-5" signage was removed from I-80 west of the I-5 junction as well as to the north.
Southbound: Before 1976, Temporary I-5 signage began near Woodland, using CA 113 south to I-80 and I-80 east to CA 99 at the present Biz 80/US 50/CA 99 interchange southeast of downtown Sacramento. Southbound CA 99 BGS signage on EB I-80 had "Temporary I-5" signage attached in order to expedite through traffic heading for the continuation of I-5 at Stockton. Post-1976, the southbound I-5 ramp to eastbound I-80/south CA 99 was also marked as "Temporary I-5"; while it's unclear whether east I-80 itself ever received temporary I-5 reassurance signage, the ramp to south CA 99 was definitely also signed "Temporary I-5". Southbound CA 99/Temporary I-5 signage mirrored northbound; Temporary I-5 exited at Charter Way and continued west to the newly-constructed I-5 alignment. I-5 itself was built as far north as Hammer Lane in the north reaches of Stockton by 1974; northbound I-5 traffic was instructed to exit at Charter Way; the stub end of I-5 was signed as "Local Traffic Only" (the southbound stub end of I-5 in Sacramento, extending down to Pocket Road, was likewise signed). The final section of I-5 between Stockton and Sacramento was completed in early 1981, at which time the temporary signage along CA 99 and its approach routes was removed.
I had moved to the Bay Area at the end of 1975; and having a big concentration of family in the Roseville/Rocklin area, I made it up to the Sacramento area often -- partly to see the progress on I-5. More often than not I used 580 over Altamont, then cut north once in the Valley -- so I got to witness first-hand the various permutations of the corridor, complete with the aforementioned "temporary" signage.