The end of the David Letterman era on ‘The Late Show’ may still be three weeks away, but the host already has a plan about what he’s going to say when he signs off on his final broadcast next month.

Speaking to the New York Times, 68 year old Letterman admitted “I know of other things that are being worked on. My only concern is mine. What will I do? And I now know exactly what I will do. And I want it to be upbeat, and I want it to be funny, and I want people to be happy that they spent the time to watch it.”

David LettermanDavid Letterman presents his final 'The Late Show' on May 20th

He’s been presenting ‘The Late Show’ on CBS for 22 years, and before that he was the presenter of ‘Late Night with David Letterman’ from 1982. Two years ago, he surpassed Johnny Carson as the longest-serving late night talk show with 31 years of presenting, and he says that he vividly remembers the way that his mentor ended his long career in 1992.

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“That was fantastic,” he reminisced. “I can remember when he signed off that night, it just left you [with] a nagging sense of loss. This doesn’t apply here. I want it to be a little more cheery.” “Of course, Johnny’s last show was historic. This one won’t be! This one, people will say: 'Ah, there you go. When’s the new guy starting?'”

Letterman is referring to Stephen Colbert, who is set to replace him on ‘The Late Show’ at some point in 2015. Colbert fronted his own satirical nightly newscast ‘The Colbert Report’ from 2005 for nine years, before retiring in December last year. But apparently, Letterman had no say in the appointment of his successor.

“I always thought Jon Stewart would have been a good choice,” he admitted, “and then Stephen.” While he was initially unhappy at not being consulted, he’s since accepted the decision as a good one.

“If you’re running the show with Jimmy Fallon, that’s a certain dynamic. Jimmy Kimmel, a completely different dynamic. And now Stephen Colbert will add a third, different dynamic to it,” he said. “I think it will be very interesting to see what he will do.” Letterman will host ‘The Late Show’ for the final time on May 20th, 2015 at 11:35pm.

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