gas tank, gas gauge, gas tank

I replaced the fuel pump on my 93 gm 1500 about 3 months ago.Since then the gas guage stopped working and a few weeks after that the gas tank started only taking about two gallons of gas and it starts overflowing like its full but it only has about 1 or 2 gallons in the tank.I HAVE CHECKED FOR CRIMPED OR RESTRICTED GAS LINES N HOSES BUT I DONT SEE ANY.  THANK YOU

Answer
    But the truck still runs, right?  I am guessing that you used a universal GM fuel pump, not a complete assembly.  The sender for the gas gauge is attached to the assembly right next to the pump.  It would be pretty easy to foul up the connection while installing the pump.  And the other symptoms indicate that the tank vent is clogged, or otherwise obstructed.  The whole thing has to come out and get checked over.  You might want to consider spending $250 for a complete replacement unit that would eliminate any possible problems.
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