Suggestions by @williamlopez

Frank Welker

as Composer in Space Jam (1986)

Quinton Flynn

as Writer in Space Jam (1986)

Chris Savino

as Producer in Space Jam (1986)

Joe Pytka

as Director in Space Jam (1986)

Maurice LaMarche

as Gossamer in Space Jam (1986)

Eric Bauza

as Henry Hawk in Space Jam (1986)

Greg Burson

as Barnyard Dawg in Space Jam (1986)

Rob Paulsen

as Marvin The Martian in Space Jam (1986)

Eric Bauza

as The Road Runner in Space Jam (1986)

Joe Alaskey

as Wile E. Coyote in Space Jam (1986)

Eric Goldberg (animator)

as Tweety in Space Jam (1986)

Stephanie Courtney

as Granny in Space Jam (1986)

Fred Armisen

as Speedy Gonzales in Space Jam (1986)

Jessica DiCicco

as Petunia Pig in Space Jam (1986)

Billy West

as Porky Pig in Space Jam (1986)

Bill Farmer

as Sylvester The Cat in Space Jam (1986)

Jim Cummings

as Taz The Tasmanian Devil in Space Jam (1986)

Nathan Lane

as Elmer Fudd in Space Jam (1986)

Kristen Wiig

as Lola Bunny in Space Jam (1986)

Fred Tatasciore

as Yosemite Sam in Space Jam (1986)