Fuel Pump problems?

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On the way back from town last night she died on me. One small backfire and the motor quit. I popped the hood and the fuel filter (clear type) was empty so I thought I ran out of gas (gotta fix that fuel gauge!). Put about 4 gallons in and it still will not crank, fuel filter is still dry. This problem is on a 78 Chevy, 1ton, 454, with dual tanks.

Is this probably a dead fuel pump?

Could the problem be with the "crossover switch" (not sure of the proper name) that controls which tank the fuel is drawn from?

Any other ideas about troubleshooting this?

Last question: When replacing the fuel pump, do I use RTV or just a gasket?