Worked with new gauge and new pumps and new tank sending unit about 6 times.
After replacing in tank sending unit and it still did not fix problem , after about 3 more temp. fixes bending float around , finally found out float was hitting on front of tank inside where the bladder had some seperation from the steel tank and bulged out just enough to make float hang up and make gas gauge indicator stick. Bent float wire back and then straight again for clearence and works fine now. A lot of hard work , most people would have gave up , about 6 months of trial and error with gauges and volt meters.
When putting sending unit back in tank it depeded on how much gas was in there as to where my float would stick , going up or going down , was 2 different places on gauge where indicator would stick at , on top of bulge or under bulge and when filling tank gauge would not show full tank or worse it would still show 3/4 tank when you are about to run out of gas.
Very Very hard to solve because you can not watch or see what float is doing or where it is with sending unit mounting plate needing to go right in the way to bolt back on. Enjoy , send to everyone.
Many many cars may have this problem.