One of Fred Willard's final interviews was for this excellent Best In Show oral history

It was more than four months ago that comic actor and frequent scene-stealer Fred Willard died. Today, one of this final interviews can be read in The Ringer’s new oral history of Best In Show, a Christopher Guest comedy many cite as one of his best. Guest, Eugene Levy, Catherine O’Hara, Parker Posey, and a number of the film’s other core cast members are also on hand, sharing stories about the scenes that got cut and the fussy dog owners they’re glad to never see again. There’s plenty of time, too, spent exploring Willard’s key role as the dog show’s charmingly boorish color commentator. Bob Balaban, for example, compares improvising with Willard to “being run over by a friendly truck.”
“You can’t make a dog show funny, or you lose the truth in the story,” Levy said, explaining that the story’s third act presented a challenge in terms of organic comedy. “And then the suggestion came: ‘Well, why don’t we make Fred Willard kind of the Joe Garagiola color commentator during the show?’ Bingo. That was it.”
Willard’s role produced some of the film’s funniest bits, his complete disinterest in the competition giving way to ramblings about Sherlock Holmes hats and dogs playing football. Willard says Guest, the director, didn’t want to know what he was going to say before any given scene. Jim Piddock, the actor playing his onscreen counterpart, was similarly in the dark, saying Willard “wouldn’t tell me what he was going to do or anything.”