The Simpsons "The Winter of His Content" from Season 25 references "Bart the General" from Season 1
The Simpsons has now been on the air for so long, they’re making their own obscure references.
The fourteenth episode of season 25 (aired on March 16, 2014 here in the USA), entitled “The Winter of His Content,” featured Nelson’s bully cronies – those two dudes I can’t remember seeing since “Bart the General” way back in season 1. The episode, which heavily parodied the film The Warriors, featured a bully convention, at which the old cronies were in attendence, which Nelson explained away by saying they’d moved to Shelbyville. If that means these guys were also in the “Lemon of Troy” episode from season 6… well, then, your memory is better than mine.
One final point: Grampa and his friends were still living in the basement at the end of the episode; did they just run out of time or is this a brave new order? It’s hard for me to believe they’re actually shaking up The Simpsons after 25 seasons, but I guess time will tell.