Why is there no power at the fuel pump on my 1986 ford e350 jamboree?

I have a 1986 ford econoline 350 jamboree motorhome. It has a 460 v8 gas motor. The fuel pump isn't working. I checked with a test light and there's no power going to the pump. I checked the inertia switch under the dash and hit the reset button and used my test light on that and there's power going in and out of it, i used to my test light on the oil pressure switch and there's power going to that. The camper won't start and was having problems with vapor lock. I checked all the fuses and tried tracing the wire from the fuel pump but i'm not sure where it goes. I did have mice in the camper that could have chewed the wire but i would need a wiring diagram for my camper. If anyone has a wiring diagram of the fuel pump on my camper i would appreciate it. Would replacing the fuel pump fix the problem? I had the switch on when i checked all the wires with my test light.

Added (1). it has a carburetor, no fuel injection

Register the truck at the AUTOZONE website and you'll have free access to wiring diagrams. Also, there absolutely no such thing as vapor lock on your fuel injected truck, don't turn your back on anybody that tells you this.

The diagrams you need can be found in any Haynes or Chilton's repair manual. The same manual covers F-150 through F-350, and E-150 to E-350.
Trucks and vans are basically the same structurally and almost identical electrically. You will have stock wiring for your fuel system. No difference if it's a camper.

Noted manuals available at most auto parts stores.