The idea about the astronaut who showed up at the Harlan high school was based on a real astronaut who had visited writer Chris Provenzano's high school, in a helicopter that landed on the baseball field.
Boyd Crowder (Walton Goggins) explains that his perfect set of veneers were courtesy of the U.S. government when he was serving in the military. In real life, Goggins had his front teeth knocked out not once but twice in childhood. The first was when he was hit in the mouth with a baseball and was taken to the emergency room, where his teeth were shoved back in (without anesthesia). The teeth healed only to be knocked out again when he was diving and hit the bottom of the pool.
The foul-mouthed rant Nicky unleashes against Ava, in which he talks about sexual favors she must have done to get where she is, was partially ad-libbed by Mike O'Malley.
Drew/Shelby (Jim Beaver) mentions that he met Arlo in Vietnam. Jim Beaver is a Vietnam veteran, immediately after graduating high school he joined the United States Marine Corps in 1968 and was trained as a microwave radio relay technician. After finishing basic training he served at Marine Corps Base Twentynine Palms, California before being transferred to the 1st Marine Division in 1970 who were stationed near Da Nang, South Vietnam as a radio operator for a forward detachment. In 1971 he as promoted to Corporal (E-4) and served as the communications company supply chief before being shipped back to the US at the end of the year and received an honorable discharge, though he remained active in the Marine Reserve until 1976.
Raylan (Timothy Olyphant) continues the Yolo "mistakes" by calling him Yoo-Hoo. Yoo-Hoo is a chocolate flavored soft drink currently manufactured by Keurig Dr. Pepper.