One of my favorite 1940s old-time radio comedies is "The Great Gildersleeve". The character was introduced on another show, "Fibber McGee and Molly", and became so popular that a spin-off was created. It may have been one of the first spin-off shows in entertainment history.
Throckmorton P. Gildersleeve was first played by veteran radio actor Harold (Hal) Peary. Peary had great voice inflection and when you hear him talk, you can just picture the character in whatever emotions were being displayed at the moment.
Several years later, due to a conflict of the show moving to another network and a contractual obligation with the previous network, Peary was replaced by Willard Waterman, another radio veteran, who'd known Peary for many years.
In 1982, I pursued both actors for an autographed photo. It's not easy to find photos of radio performers, so for both requests, I only sent the usual return envelope. Harold Peary sent me a great 8x10 which featured him in four facial expressions. Willard Waterman was "Happy to oblige" my request, and sent two photos, seen here and here.
If you'd like to listen to some of the radio shows, you can do so here.
And here's an entertaining book about the show.
Side note: In the early 1970s, I wrote to Jim Jordan, who played 'Fibber McGee'. His real-life wife Marian (who died in 1961)) played his wife 'Molly'. I requested a photo, and this is what he sent.