Bubbles' flyer for the model train convention advertises the "Swayzie Express" - the misspelling was intentional, as Patrick Swayze did not authorize TPB's use of his name.
The lotto sign in the truck stop is for Lotto 420. 420 is the universal code for Marijuana.
The sign Bubbles pins on his shed door reads: "Dear Boys: Ray is Driving me to Maine to make a little money on scrap and I'm going to that train convention I told you about. I know you guys are busy so I didn't ask you to come. I need you to feed Shitrock and the Purv Monsters. Bubbles."