I have a 1999 Plymouth Voyager, and I have found the wiring diagram in the back of my Haynes repair manual. These are commonly found in any auo repair shop. I'm sure they have one out for a 2004 Dodge Caravan.
The fuel tank is just the tank itself. With the fuel pump built into the tank. Remove the tank by draining as much gas as you can out first via siphon. Support tank and remove the retaining strap bolts. Carefully lower and remove the wiring and fuel lines.