If you're referring to a car registered and insured to drive on the street (by the term street car), many states have laws against anything that does not have a DOT approved mark on it. You may want to double-check with the DMV in your area.
I had a VW Type 181 (Thing) that failed NJ state inspection because the windows were lexan, not the approved material - I should have left the windows at home
Just my $.02