i am looking to do the big 3 on my F-350. i don't have a system in the truck nor do i plan to install one. i want to do the big three to help with the voltage pulls the components on the truck draw (glow plugs, a cold FICM). there are 2 batteries and i believe the primary is the passenger side. should i do the big 3 on each battery or just the primary. i was trying to find some wire diagrams of the charging system, but haven't been able to locate any.
