if your fuel pump isn't working, you'll know when you turn the key just to on without trying to start. it should hum for about 2 seconds. if not, check the voltage at the connector under the car where it goes into the gas tank. if you have voltage, your pump is gone. you might try cutting a hole in the floor above the gas tank with tin snips so you can change the pump without dropping the tank. be careful though. The computer cycles the pump for a few seconds until pressure is built up in the system. this happens when the key is turned to the on possition. the computer has two fuses usually a 15 amp and a 10 amp fuse. one of these fuses makes the relay hot at all times. the pressure return regulator and throttle control send signals to the pump telling it how much fuel is needed to operate the car. there is on most models a bypass wire located under the hood passenger side. the manufacture recomends you take a wire connect it to a ten amp fuse and directly power the pump. if you dont hear it run replace the pump.
I may be wrong but I own a 92 RS 305 there is a fuel pump relay under the hood next to the firewall on passanger side. Not sure for V6 tho.