As a college intern at adult pop radio station WBMX/Boston, this author had the privilege of meeting Kasem in 1995 when the signal signed on as an affiliate. While he was recording liners for his show, I summoned the courage to ask Kasem if would also include one for my shift (a countdown, naturally) on Boston University's WTBU. Kasem politely declined, citing contractual issues. Instead of being disappointed, however, I was simply happy to have spoken with the legend.
After finishing the session, before turning away from the mic, Kasem remembered the eager intern still in the room. He said while he couldn't endorse a station not airing his show, he could offer a compromise.
To this day, a brief recording of "Hi, this is Casey Kasem, and you're listening to Gary Trust!" remains a prized possession.