Diagram for the cabin battery hookup needed

Acquired a E350 Cutaway RV. It came with no batteries. Looking for cabin battery hookup diagram (has about seven connections) also, has two solenoids that look like starter solenoids.
First question, will the vehicle start with out cabin battery installed (because I have no voltage driving the fuel pump circuit?
Second question, what is the second starter solenoid for?
Aide in starting of engine or used for a circuit passing or possible for generator start?
Having trouble finding correct diagrams for that year.