Wisconsinites all love Wisconsin jokes and ethnic jokes as we are all ethnic. No snooties here.
So to your question. First I have to ask where do you live? Urban types might find my advice a little more difficult to accomplish as they have smog testing to deal with. What I would do is select a donor that doesn't require smog testing, like a '67 AH Sprite or similar. Then find one with an unsalvageable rusted out body, Easy. Make sure it has a good clear title. Start or better continue paying for plates. Build car. Attach plates. Drive
You now own a '67 AH Sprite with custom bodywork. You might evan drop in a different engine, gearbox or whatever. Make sure your pipes are quiet. This may be the land of Harleys but you want quiet. And when the officer asks, it is a special bodied AH Sprite and be friendly. Actually, where I live, the cops already know what I am building.