i have an 87 lx with a 93 cluster and harness, the gas gauge doesnt work so i changed the sending unit and it still doesnt work,. i was told its the anti slosh module, does anyone know if this can be removed from the cluster and changed or does the entire cluster need to be replaced?

I replaced the sending unit in gas tank and I replaced anti slosh module in dash. when I turned the car on it said I had a half a tank. I went to the gas station to top her off and it held 5 bucks. Got in and guage says 3/4 tank???? I drove her a few miles and the gauge seems to be getting lower...