Loved this site. I marked the first one we came to which is where we stayed, but there should be much more just down the road. There's at least one that you can drive to that's practically on the rim. The position marked is near a paved trail head and parking area that includes a vault toilet, we chose that spot for that reason alone. If you want to be closer to the rim, there are many more FS roads off the main road further south that I'm certain has more opportunities for dispersed/car camping. Highly recommend getting up early and catching that sunrise over the rim.

Since the drive in is so specific only to the North Rim, here's our approach to the site, and a little bit of the sunrise.