Anyone have any Pinewood Derby tips/tricks?

When I was in scouts I did the pinewood derby twice. I don't know if this is legal anymore, but we cut the part of the car out of the block that was going to be for the front axles. I'm not sure now if we redrilled the axle holes or not, but then ran a very small bolt and nut through this block through the top of the car. This allowed us to bolt this block of wood back up to the car and then "align" it so that it went straight. I would run it across the floor, see which way it turned, and then adjust as needed.

We did this alignment trick both years and never got in trouble for it. We did get disqualified the first year (they let us keep the trophy for winning, but didn't let us move on to the next level) because we sanded the tires down to narrow little points. The car was wicked fast.