Senoir Project

I am now a freshman in high school. The subject has just come up about senoir projects to graduate. I was kicking around the idea of restoring a car. I was just wondering if you had any suggestions on what type of car I could buy to restore. This would be my first experience rebuilding a car, but my dad and my neighbor both would be more than happy to help me out. It can't be too expensive....lets say up to 3000 for the car not counting the parts. Any advice or suggestions would be apreciated.

70's caprice, impala, or cadillac
70's GMC Pickup

ford crown victoria..like an old cop car..those things go like stink

Datsun Z series