Pancho Lopez started guiding sheep hunters in 1970 and guided over 200 sheep hunts in Baja California Sur, the southern ranges of Baja California near Bahia de los Angeles; and in Sonora on Tiburon Island. In 1998, Pancho guided Gary Hansen on Tiburon Island's first bighorn sheep hunt. Subsequently, he guided Butch Kuflak to his 193 4/8 (green score) ram and George Harm to a 181 6/8 (green score) archery ram. Pancho's last sheep hunt was in 2006. He passed away on November 28, 2010.
Pancho's youngest son, Francisco, is currently pursuing a PhD at the Autonomous University of Baja California to work on behalf of bighorn sheep and bighorn sheep hunters in Mexico.