To illustrate the difference between KMPC as an MOR and KMPC as an AC, I've got two Gary Owens airchecks---one from 1970, the other from 1973.
Let's look at what records he played. These are both Saturday shows, so he's playing more records per hour than he would on a weekday show:
November 28, 1970:
4:30-5:00 pm
(News)
George Russell: In Laguna (guitar instrumental)
Bobby Sherman: Easy Come, Easy Go (early 1970---peaked at #8 at KHJ)
Claudine Longet: I'll Be There (cover of the Jackson 5 hit)
Chicago: Does Anybody Really Know What Time It Is ( the only current chart record in this half-hour, which Gary describes as having "a Four Freshmen-type of sound")
Ferlin Husky: Sweet Misery (a current, but only charted Country)
The Renaissance: There's Always Something There to Remind Me (a vocal group using baroque-styled arrangements and singing no words---just "ba-ba-da-ba-da")
5:00-5:30 pm
(News)
Five Flights Up: After The Feeling Is Gone (a current---but a stiff--peaked at #89 on the Hot 100)
Peter Nero: Summer Me, Winter Me (piano instrumental)
The Crystal Mansion: Carolina In My Mind (vocal group cover of James Taylor song)
Dionne Warwick: Alfie
The newscast at the top of the hour is longer, and there were some Sigalerts because of crashes in the rain, so the 5:00 half hour had fewer songs than the 4:30.
June 16, 1973:
4:00-4:30 pm
(News)
Stevie Wonder: You Are The Sunshine Of My Life (current)
Matthews' Southern Comfort: Woodstock (1971---peaked at #8 at KHJ)
The Big Bopper: Chantilly Lace (1958)
Freddie Hart: Easy Lovin' (1971---peaked at #19 at KHJ)
Henry Mancini: Theme from "Oklahoma Crude" (instrumental)
4:30-5:00 pm
(News)
Jan & Dean: Surf City (1963)
Tommy Edwards: It's All In The Game (1958)
Arlo Guthrie: Gypsy Davy (current)
Carpenters: Yesterday Once More (current)
Patrick Williams: Like Always (instrumental)
So, three pop chart currents in an hour compared to two three years earlier.
Five Goldens that had Top 40 play in the market (at KFWB, KRLA and KHJ) compared to two in 1970 (though Dionne Warwick's "Alfie" was a bigger record for KMPC when it was new than it was for KHJ, where it stalled at #17 and was only played for four weeks).
No more covers of pop hits.
Instrumentals moved from within the half hour to leading up to the newscast (both Mancini and Williams were pre-rolled to hit the top of the hour, and faded in when the commercials were over).
It looks pretty tame from 50 years out, but at the time, it was a significant shift---and sent many of KMPC's 50-plus listeners to Beautiful Music stations (which, with XTRA and KPOL, could be found on AM as well as the FM choices like KBIG, KOST, KWST and KLVE).