[Zeke]

You might consider using some of the Boxster chassis. I have no idea what body work you have in mind, but the box has AL hoods and the basic monocoque is not a lot more heavy than a bunch of steel tubing. Remember that these cars handle very well on relatively big tires, so the stresses are large. That will take a substantial tube frame to equal the stiffness of the box. If you remove every non essential part from the car, it will be light. And, it will be a lot easier to register with your state DMV.