In June 1989, all four Monkees appeared on The Mark and Brian Show on 95.5 KLOS FM in Los Angeles, California. The band was promoting its July California appearances and the Hollywood Walk of Fame ceremony. (They also sang "Papa Gene's Blues" and "Daydream Believer" on air.) Check out the audio of the program posted in the 1989 North American/Japanese Tour section. Also posted (at the very bottom of the 1989 page) is a radio station promo ad for Monkees concerts in San Diego in July 1989.
I also posted more videos on the Live Almanac's YouTube Channel here.