Credit: Fox

UPDATED: Fox and The Simpsons producers are making some changes to Sunday’s programming to pay tribute to the passing of longtime Simpsons actress Marcia Wallace.

First, the network is replacing a repeat of American Dad with a previous Simpsons episode that focused on Wallace’s beloved character Edna Krabappel.

The network will re-air the episode “The Ned-Liest Catch,” the show’s 22nd season finale. In the episode, Krabappel is suspended from school and starts dating Ned Flanders. The network originally announced plans to re-air Wallace’s Emmy-winning episode from the show’s third season, “Bart the Lover,” but “technical issues” clearing the 20-year-old episode prevented the last-minute switch and a newer episode featuring her character had to be chosen instead. the 16th episode of the show’s third season, “Bart the Lover,” which offered a sympathetic take on Bart’s cynical, lonely teacher. In the episode, Bart discovers Krabappel has posted a personal ad, so he begins writing her bogus love letters. After setting her up on a fake date, he spies her sitting by herself in the restaurant. When she’s still there hours later, he’s no longer amused by his prank and sets about trying to make things right.

“The Ned-Liest Catch” will air as the 7:30 p.m. lead-in to an all-new Simpsons, titled “4 Regrettings and a Funeral.” The new episode will then conclude with a tribute card from the producers honoring Wallace. Also, the episode opens with an epic-length couch-gag spoof of The Hobbit (video here).

Wallace died at age 70. “I was tremendously saddened to learn this morning of the passing of the brilliant and gracious Marcia Wallace,” producer Al Jean said in a statement earlier this week. “She was beloved by all at The Simpsons and we intend to retire her irreplaceable character.”