IndyCar fanatic, owner David Letterman drives into retirement with tribute car at Indy 500

In this image released by CBS, David Letterman appears during a taping of his final "Late Show with David Letterman," Wednesday, May 20, 2015 at the Ed Sullivan Theater in New York. After 33 years in late night television, 6,028 broadcasts, nearly 20,000 total guest appearances, 16 Emmy Awards and more than 4,600 career Top Ten Lists, David Letterman is retiring. (Jeffrey R. Staab/CBS via AP) (The Associated Press)

Fans wait outside The Ed Sullivan Theater during the last taping of the "Late Show with David Letterman" on Wednesday, May 20, 2015, in New York. (Photo by Charles Sykes/Invision/AP) (The Associated Press)

Before the freshly retired David Letterman drives off into the sunset, he's set for a trip at the Indianapolis 500.

Letterman's IndyCar race team paid tribute to the former "Late Show" host by putting a caricature of his face and #thanksdave on the car of driver Oriol Servia for Sunday's race.

Team members wore gray T-shirts with their own "Top Ten" list of reasons they love Letterman. Among them: Cries on the parade lap.

Letterman says of the tribute, "with everything that's happened, it's the highlight of my career. It's crazy it's the Indianapolis 500."