707 Hell Cat, what does it mean?

I just realized something about this fancy new factory hot rod. ........I'm guessing......you can't show up at the local track and run it because IT HAS TO HAVE A CAGE!!!???!?!

apparently the rule book says if the car is untouched then it doesn't need a cage. now how close the techs at different tracks interpret it should be interesting. will they let a set of slicks by? who knows. could vary track to track..