I've got a slightly modified Mustang that I show pretty regularly. I started out with a totally stock vehicle and added a few mods along the way: wheels, exhaust, etc.
The biggest compliment I get is the cleanliness and finish of the car. It's got 14,000 on the odometer and most judges comment on the undercarriage which is spotless. Also, the paint finish is now flawless.
I've found the spectators go for the wild customs (from a visual standpoint, they stand out) and judges go for cleanliness of the vehicle.
After 3 years of showing, I've gotten a lot of 1st, 2nd, 3rd, Top 20, etc and it's fun.
I'm currently working on a detailed undercarriage: fully polished exhaust tubing and mufflers (done), painted axle assembly (standard Detroit rust), and an aluminum driveshaft (to replace the standard rusty steel one). Not extravagant by any means, but a nice, neat appearance.
Have fun at the shows and be proud of your ride!
Totoland Mach