Fuel Pump Not Working

1999 Chev S10, 4.3L, 175,000km, 2wd, auto.
I just purchased the truck, was told it needed a new rad and fuel pump, it didn't start when it was damp outside.
I drove the truck a couple of days, then changed the rad, fired up the truck and changed coolant.
I then changed the plugs, wires (identified each, should not be any problem there), cap & rotor.
Truck would not start, it was late in the evening and somewhat damp.
The next day, I checked fuel pressure on the line, 0 reading. Then checked fuses (OK), changed relay with several others from the fuse block (no change).
I then pulled the bed to work on the fuel pump. There are seven wires @ the tank, four to the pump/gauge assembly and three to another block. Voltmeter shows 5.14V on one gauge terminal and the same on the gray wire on other block, no voltage to pump. I then ran direct from the battery to the pump, +positve to the gray wire, -negative to the black wire, pump did not work. Help!

Steve
Hamilton, On