How about a 62-65 Nova/Chevy II? These are good looking rides, nice and light, plenty of parts around for them. Then find a 400 small block and a powerglide or T350 and you will have a very quick ride for not a lot of money. If there is a problem with these cars it's getting a decent tire under them, but they respond well to bolt on traction bars. If you really want to build a sleeper, find a 4 door or a wagon.

Pat