Thank you, Chris -- but the document does not indicate whether or not there are any parking restriction signs. (Although the document will help in other ways.)
I will be hiking a day hike from the north rim to the south rim, with my vehicle remaining on the north rim. I will be taking the shuttle back to the north rim the next day.
I was originally planning to take the shuttle the Grand Canyon Lodge offers at 5:45 AM to the North Kaibab trailhead to begin my hike, and leaving my vehicle parked on hotel grounds. However, I now think I want to start my hike earlier. Therefore, to avoid a 1 1/2 to 2 mile walk to the trailhead (and conserve energy for the 24 miles rim to rim), I wonder if I can park my vehicle at the trailhead parking lot from the morning of one day until early evening the next (when the rim to rim shuttle arrives) -- thus my original question, are there any signs at that north rim parking lot indicating overnight or otherwise parking restrictions?