The US rural population is 15% of total population and declining ( "About 46.2 million people, or 15 percent of the U.S. population, reside in rural counties, which spread across 72 percent of the nation's land area" https://www.yahoo.com/news/census-rural-us-loses-population-... )

Next rural population has plenty of vehicles that use gas that could be electric. For example, 4wheel ATVs. A farmer that has an electric ATV could power the ATV with a solar array. Or an electric tractor, water pumps, etc

Lots of opportunity to take ICEs out of the mix. Not just the pickup truck.