The border post
And here's what Wikipedia has to say:
Antelope Wells is a small unincorporated community in the state of New Mexico in the United States of America, located along the United States-Mexico border, across from the small settlement of El Berrendo, Chihuahua, Mexico. Despite its name, there are neither antelope nor wells in the area. The name comes from an old ranch, located 2.5 miles north of the current community. The only inhabitants are United States Customs and Border Protection employees.
Antelope Wells is the southernmost settlement of New Mexico, situated in Hidalgo County and in the region commonly known as the "boot heel" of New Mexico. It is the smallest and least-used border crossing of the 43 ports of entry along the border with Mexico. The crossing, which is open solely for non-commercial traffic, is open every day from 8 in the morning to 4 in the afternoon.
The port was established by Ulysses S. Grant in 1872 and has been staffed since 1928. In 1981 the border crossing had a population of 2, living in trailers behind the customs station, and averaged three people enterring per day. In 2005 just 93 pedestrians crossed over at the site, which consisted of just four buildings, a port of entry building, two houses and a trailer. Including domestic and international travelers, fewer than 500 buses and privately-owned vehicles pass through the community each month, though traffic has been increasing slightly lately with more international shuttle van service. Despite its low usage, there is no move to close the port, which is the only port between Douglas, Arizona, and Columbus, New Mexico, and provides the most direct route from the United States to the Sierra Madre Occidental.
Antelope Wells is located on New Mexico State Road 81, which links it with Interstate 10 and New Mexico State Road 9. Antelope Wells is the official southern starting point of the 3100-mile Continental Divide Trail.
The word from Sarah is that they are expecting him to finish roughly Wednesday lunchtime New Mexico time.
So that would be around 6am Thursday morning in New Zealand.