Its very unusual for a failing pump to cause fuel starvation symptoms for anything more than a few minutes before it fails completely. They tend to work, and then don't. Your description implies something other than the spinny bit - plumbing or similar.
Running out at 1/4 tank is very common - usually either incorrectly fitted, or the wrong pump. Duff seals on the pump assembly can cause the inlet to cavitate at low fuel levels, but the pump is completely submerged at 3/4. Quite odd for it to fail at that level, unless its just a crap pump like a Magnetti Marelli which tends to work for ten minutes then burns out.
Normally after changing the pump at 1/2 tank or less it needs a gallon or so throwing in to prime the pump bowl but then it should be fine.
If you're taking it out again, make sure the return line is tucked in to the fuel pump bowl. If thats just discharging off to the side that can cause issues.
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