The timeline for the movie is the early 80's. William Lane Craig was only beginning his research into the Resurrection during that time under Wolfhart Pannenberg. He didn't publish his doctoral thesis on the topic until 1984/5.
The day of his father's funeral, Lee removes his father's Illinois driver's license from the wallet. It's a color, plastic, photo ID with dad's picture, but in that year, Illinois Driver's licenses were a piece of paper with typing on it. No photo and not plastic.
In Chapter 9, minute 55.6, when Lee and family are driving home their station wagon front license plates are orange/yellow with dark lettering. The Illinois plates for that year (1980) were dark blue letters on a reflective white background.