The red car that they take on the road trip contains the letters DNR which stands for Do Not Resuscitate. This is a legal order to allow natural death.
According to director Alex Lehmann, the Kung Fu film titled "Death Punch" watched by Michael and Andy numerous times, is actually fictional and was produced just for this movie. You can see the two main protagonists of the film, credited under the movie's Cast & Crew as well.
The European-style tourist town that Andy and Mike drive to is Solvang, California.