No need. As KM says, only call letter freaks would care. "KFRC" means nothing in L.A. And having those calls on KCBS' FM simulcast sure doesn't keep them from having a great top-of-the-hour ID:
http://www.tophour.com/audio/San%20Francisco-San%20Jose%20CA/am0740_2014-12_kcbs_sfybush.mp3
And CBS is doing nice stuff with KFRC HD-2, playing classic hits with an emphasis on stuff that was big on KFRC in the 70s and early 80s with IDs and jingles from back in the day. Driving around San Francisco, it sounds about right...only missing the jocks:
http://player.radio.com/listen/station/kfrccom-classic-hits
In regard to KFRC HD-2, they are playing the exact same music and ID bed/jingles that we used on 106.9 when it was live with jocks. What little imaging they are still using on HD-2 is stuff I threw together in '08...the good sweepers either rarely play or have been removed. I wasn't even aware it still existed.