Helping with local car show. Looking for advice/ideas

You don't say how many cars you get, but if it's no more than 300 I would ask the entrants to be judges. One from each of the big 3 type cars and one for imports and one for pre 50's cars. Have each of them pick their top 10 and hand out trophy's to the highest vote getters. I would also have each entrant pick their choice for best in show. Car with the most votes wins. That way you don't have a bias toward any one type or style of car.

Jack