Ah, you should have called me...I won three years straight with a car I built and my kid did it twice. My dad would show me how to do something and I'd go do it. I graduated to taping my stripes as you can see.
My original cars in order of year (bet you can't tell I LOVED Grand Prix racing!):

My son's (missing his "Herbie" F1 car):

I won best paint in the "Dad's Division" with this:

Of course, I beat all of the other Cub Scout leaders in our "Dad's Division" with this:

The Chevelle is pretty much hollow inside to hit 5 ounces.
Can't tell I love Pinewood Derbys...can you?