Used wheelchairs, only 3,500 miles, road tested.

It was in two such vehicles that Phil Carpenter and George Murray, aching for sleep, wheeled into the Virginia hunt country near Warrenton after dawn yesterday, trailed by a van with flashing lights.

It's a long way from Los Angeles.

Carpenter and Murray, both champion wheelchair marathoners, are on the last portion of what they say is the first continental crossing in hand-powered chairs. Paralyzed from the waist down, they've rolled through deserts, mountains and floods at a rate of about 50 miles a day since April when they left the Santa Monica Pier bound for New York.

"Sleeping has been our biggest problem," said Murray, a 33-year-old physical education student at the University of South Florida, who was resting yesterday at the Westpark Hotel at Tysons Corner, where he was met by Fairfax Board Chairman John F. Herrity. "I mean getting it."

In the Mojave desert, it was rattlesnakes.

The reason for their trip, they explained, is to show that "people who have a disability can be physically fit. Being in a wheelchair doesn't mean losing your mobility."

They've had plenty of that in their custom-built vehicles, especially on the downside of the five mountains they crossed, tearing into hairpin turns at 45 mph, trailing makeshift parachutes for drag.

"There's only two things we don't do," says Carpenter, a 34-year-old Florida resident who broke his back nine years ago in a water skiing mishap. "We don't do windows, and we don't do gravel."