In NJ there are 2 options for older vehicles you can register it as historic no inspection you do need to show a photo when you get the plates. with historic they are only supposed to be for going to shows but I drive my vehicles around and never had a problem. The 2nd option is register as a classic you can only drive 3000 mi per year again and do need to show up one a year to have milage checked below is a link to the njdmv
NJ DMV Historic plates Now for my 2 cents on a project. I would try to find something with a good body no major rust or cancer and a truck that is running you will pay a little more but it sounds like you already have your hands full. Also kids looks for quick results and minor repairs will keep there attention longer then a 6 month to 1 year restoration
