Pinch-Hitting Note: The "Pink Panther" series of films is one of the most durable in screen history. They continue to unroll in the slapstick imagination of Blake Edwards regardless of death -- Peter Sellers' -- or, in the case of the recently completed "Trail of the Pink Panther," illness. David Niven was to do some post-production voice-over but was having trouble with his voice. So impressionist Rich Little was called upon to do Niven's voice . . . Or so Little told a Canadian radio announcer. Niven's manager says the star is in perfect health. In any case, Edwards is reported to be upset that Little went public about the assignment, which was to have been a secret . . .
Branching-Out Note: Loudon Wainwright III, guitar-strumming author of classic songs such as "Dead Skunk," is moving from the folk-club circuit to Broadway. He is about to become a Pump Boy in the country-rocking musical "Pump Boys and Dinettes" . . .
Continuing Hiatus Note: Robert Altman, wandering iconoclastic director, continues to explore other mediums. After an unsuccessful fling directing on Broadway earlier this year ("Come Back to the Five and Dime, Jimmy Dean, Jimmy Dean"), his next project will be to direct Igor Stravinsky's opera, "The Rake's Progress" Nov. 5 at the University of Michigan in Ann Arbor . . .
Clean Up Your Act Note: When it was released last summer, "Excalibur," John Boorman's telling of the Arthurian legend, earned an R rating for its stylized violence and nudity . . . the film has been re-edited and reclassified by the MPAA. It can now be released as PG . . .