There were only a few places where I found services to be few and far between. You may want to try a couple of detours from the ACA route. One is from Safford, AZ to Silver City, NM. Instead of the ACA route follow hwy 70 all the way to Lordsburgh, NM. The road is good and there are limited services in Duncan along the way. Then take hwy 90 up to Silver City to rejoin the ACA route. The other detour is taking hwy 90 from Van Horn, TX. The road is good with little traffic but there aren't any services between Van Horn and Marfa so carry everything you need for the approximately 75 miles. As was mentioned earlier there are few spots where you will travel more than 40 miles between services and those are indicated on the ACA maps.