First find a wiring diagram for your truck. Next let us know exactly what the problems are. Looks like someone has done some replacing all ready. That always making wiring problems intresting.
Hard to tell for sure but it looks like somebody made a tab off of the hot post and attached circuit breakers to supply juice to something. Also from the color on those white wires they've been hot, could be that rusty connection. Anything ran off of the other lugs of the breakers? If they aren't hooked to anything your using ditch them, I'd ditch them anyways.