I've got one pic of a vehicle in the crappy 1989 movie "Ginger Ale Afternoon" which is only worthy for a nude scene with Yeardley Smith.
http://www.imdb.com/title/tt0097432/
Otherwise, here's a link to scene of Yeardley & John M. Jackson sitting on the front bumper of a 1947-53 Chevrolet 6700 School Bus, converted into an RV:
http://www.mrskin.com/data/star/00/05/27/biopic2_686.jpg
The source of this isn't exactly family-friendly. It's from the Mr. Skin website, a site dedicated to nude scenes in movies and TV shows:
http://tour.mrskin.com/Stars/00527/Yeardley_Smith.htm?nats=MTM5MDU6Mzox,0,0,0,0