Ok, I think I'm going to enter this with a Buick Regal...
Thought about using either a Grand National Or Monte Carlo SS chassis, but both are too narrow. What I will do is find a pair of high back seats, cut the window net out of the cage, and maybe try to use the stock Regal dash. So far I've filled all the hood pins and removed the front and rear window straps.
I think I will leave interior black or dark gray to somewhat help mask the cage. Not sure what color to paint exterior. Thinking cream, medium blue, or charcoal gray. Will probably use the NASCAR slicks with these wheels
Will have to try to figure out what to do for tail lights. Not talented enough to graph the GN rear end to body. May use BMF and paint in tail lights