Here's a few ideas from other shows:
As mentioned, Moparfest gives away 2 cars, one for the participants and one for anyone that buys a raffle ticket throughout the year. I believe the proceeds all go to charity. Why not hook up with a charity doing a raffle for a Mopar, and have the live drawing at the event? They also have 50/50, engine burnout contest, and live music throughout the day.
Syracuse Nationals has drawings every hour using program numbers and numbered tickets given to participants in their goody bags. These tickets are dropped off each day by the participants and used throughout the day for the drawings. They also give out a "street rod" every year which all the parts and labor are donated by the vendors and sponsors. The daily Sunday tickets are drawn from to find 10 contestants eligible to win the car. They randomly get from 10 t0 1 and the winner must have a registered car on the show field. They have a lot of recycling cans for cans and bottles.

I think you have a great show and I'm not implying you copy others, but these are just some suggestions. Getting the registration done on Thursday was good, but by mail it would even be better.
Thanks,
Jim

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