When Shawn and crew are standing outside "White Rock Muffler", they're really in White Rock, BC just outside Vancouver.
Hidden Pineapple: Painted on the wall of the cave. KPS - 1-29-17. There is also a plastic pineapple on the table when Shawn calls Henry for help.
Spot the pineapple: At the start of the scene where Shawn, Henry, Gus and Jack are going through Henry's ransacked loungeroom, there is a toy pineapple at the bottom left of the screen as the camera pans across.
Frank, Dean, Sammy, and Joey are references to Frank Sinatra, Dean Martin, Sammy Davis, Jr., and Joey Bishop. Also know as The Rat Pack.
Uncle Jack used to take Shawn and Gus to Red Robin when they were kids, which Shawn confirms, though in a previous episode, Shawn is interested in a woman whose favorite restaurant is Red Robin and he mentions he doesn't know what is even served there