The advice that Spirit gives Bear from his mom, including "You know when I was young, my mom, she told me" "take your time, don't live too fast" "remember there is a Creator always up above" "Don't you worry, you'll find yourself" and "follow your heart if nothing else" are either a play on or directly lifted from Lynyrd Skynyrd's song "Simple Man."
The Rez Dogs were not at the Amarillo bus station. The Amarillo Greyhound station is in a large building in downtown Amarillo, surrounded by other large buildings.
The bus passenger Cheese talks to is drinking an orange Faygo. Faygo is not a generic entertainment industry brand; it's a real life brand based out of Detroit, where it's called "pop", not "soda".