Towards the end of Luke Perry's Guide to Love, in the restaurant scene various girls from other previous episodes can be seen. The easiest ones to spot are Melinda, the black girl from Candidate Johnny, Helga from the episode To Helga and Back, and the lady wearing pink from the episode Charm School Johnny, where she confronts Johnny about not being a gentleman.
Master Hama (after Johnny breaks some mirrors): You idiot! That's 191 years of bad luck!
Johnny: You're Fidel Castro!
Luke Perry: I'm Luke Perry.
Johnny: Right. What did I say?
Johnny: Wait! Don't go! I'm your biggest fan, I've admired you and the rest of the cast on Baywatch!
Luke Perry: Don't you mean Beverly Hills 90210?
Luke Perry: Well, Johnny, on a scale of one to ten... you're an idiot.
Johnny: Cool, Luke Perry likes me! (pats him on the back and accidentally pushes him off the tree branch they were standing on)
Animation Studios: All episodes this season (except for the Valentine's Day and Christmas Specials), were done by Koko Enterprises.
This is Luke Perry's first and only appearance on the show.
The episode Fugitive Johnny, and especially the search for the "two-armed man" refer to the 60's series The Fugitive, as well as the 1993 film directed by Andrew Davis and starring Harrison Ford and Tommy Lee Jones.
In these, Dr. Richard Kimble searched for an elusive one-armed man to clear his name of murder charges.
Luke Perry: Don't you mean Beverly Hills 90201? This is a reference to the real-life television show, Beverly Hills, 90210, which aired between 1990 and 2000.
The title of the episode In the Line of Johnny is a spoof on the title of the 1993 movie In the Line of Fire, directed by Wolfgang Petersen and starring Clint Eastwood.