So here's the deal with KCRA themes...
In that clip the pre-show teaser music dates from about 1983/84. There was an open that used it as a basis, and a number of bumper cues. Around 1986 a more majestic set of opens were composed, but the other cues remained.
See here in 1985 the original open
See here in 1987 the pre-show, 1986 open, and bumpers
Then, in 1988 a jazzier package of bumpers was created (seen in the open and close of the 1990 clip) that remained in use until mid 1990 or so, but the 1983/84 pre-show music remained.
Then that 1990-92 package came about, when they went to '24 hour news,' but I think the 1983 pre-show stayed in place.
Finally in 1992 for the early prime shift the package was completely reworked.
It was a great set of cues those 9 years or so...wish they turned up somewhere. In my top 5 of best packages.