I went through the process of enhanced inspection to get a reconstructed title on a Jeep I sank. You can build a car and get a title. I went through a process trying to get insurance on a tube frame rock crawler and not having a vin was a problem, but I was not about to put fenders, lights and a horn on a competition buggy just to get a vin. I would prefer to register it as an antique after going over it to be sure it is safe and fit for use.
I am am also looking for semi local folks that are familiar with maintenance issues like bushings and brakes and other stuff I might not know to keep an eye on.