The waiter who serves The Gang first appeared in the episode "Sweet Dee has a Heart Attack" as the man who hires Mac and Charlie into the mailroom.
The building in which Guginos is set is the same building used for the original set of Paddy's Pub in the first 2 seasons, until they built a proper set.
The episode takes place in a restaurant called Gugino's. This restaurant is first mentioned in Gun Fever (2005) as the location of Sweet Dee's and Colin's date.
Approximately 3 minutes 21 seconds into the episode, a piece of music is used as underscore that appears to be an adaptation of the Pizza Theme from the Spider-man 2 video game. There is no crossover between the music department of the show and the game.-- The piece is better known as Funiculì, Funiculà by Luigi Denza, composed in 1880, 124 years before the Spiderman 2 video game.