Scott, good to see that you're coming! If you arrive Thursday afternoon, you'll have no problem getting in and getting set up. They typically stop parking rigs around 10 or 11 that night. As for your wife, if she shows up any later than about that time, she won't be able to get in until the next morning. You shouldn't have any trouble walking the track in the evening.

There's also a lot of ARRC in-car video footage up on youtube you can watch. I myself have two or three of the previous years races up there.