NJ has made changes to their child seat rules.
NJ Child seat rules
I am not a lawyer, but here is the first sentence:
Every person operating a motor vehicle, other than a school bus, equipped with safety belts or a......
I am pretty sure it clearly states the law only applies to motor vehicles equipped with safety belts. This should be important for people who are in NJ and operating without seat belts. You will want to keep a copy of the law on hand to show it is probably legal for you to transport children in you car without seat belts since the car was produced before seat belts.
I will state that I have installed seat belts in my cars without belts as I prefer to not take chances.
I realize a lot of people want to take the kids out for a drive and it would be smart to know the law. My kids have gone around the neighborhood in my brothers coupe without seat belts.