This song was originally conceived as "Ginny On My Mind," written by Jan Berry, Tom Sumner, and Alan Wolfson. Jan later changed the title to "Diane's On My Mind," to reflect his new relationship with Diane Osborne in 1977.
The instrumental backing track, performed by Wrecking Crew musicians, was fully finished in the studio. Lyrics were written, but the vocals were never finished.
However, Tom Sumner instigated a re-write, recasting it in the vein of a John Denver song. The new title was "California Sunshine." They changed the lyrics and recorded a rough demo (without the Wrecking Crew).
The original backing track for "Ginny On My Mind" (Wrecking Crew) is strong, and I hope to get it released some day.
Just FYI . . . The backing track for the song "California Sunshine" on the Jan Berry tribute album I co-produced was faithful to "Ginny On My Mind," but vocalist Robbin Thompson changed the melody of the lead vocal to reflect his personal style.
For those who don't know, Robbin Thompson was the lead singer in Bruce Springsteen's band called Steel Mill in the early '70s (before the E Street Band). Robbin then went on to front his own combo, the Robbin Thompson Band. The group had a Billboard chart record with "Brite Eyes" in 1980 (#66).
Backing vocalists for Robbin Thompson's albums included Rick Roberts of The Flying Burrito Brothers and Firefall ("You Are the Woman"), and Timothy B. Schmit of Poco and the Eagles.