Heck, I would have killed for ANY car to drive to school when I was 16! I was either on the bus or at the mercy of my friends until I was a junior. Then i got the old family truckster so I could go to work after school. I think your kid has a lot to be proud of. The fact that he will be driving. The fact that he will be driving a classic Mopar. The fact that he put so much effort into his own ride. And the fact that his Dad helped him do it. You should be proud too!
Oh, and X2 on the seatbelts. Just because a kid loves his car does not mean that he will always have the best judgement!