I actually use the outside tank, and the single tanks before I use the 2nd inner tank. My main reason for that is that its much more difficult removing the 2nd tank on the slide than it is removing the single or the outter tank. Just how I am doing it, but I still use it as a "Backup"
2013 Columbus 295RL
2006 F350 6.0L Crew Cab LB SRW