Vast majority of electrical issues in these older vehicles is poor connections. Majority of those are in the daisy chain of parts and hardware that create a ground path.
Your search here will find a lot of posts about inaccurate aftermarket senders. What's missing from those is details about what the gauge was doing or not doing with the original sender. It boils down to owners assuming or guessing where he fault is and/or which part is easiest to replace. Fuel gauge wrong ? Sender R&R is easier that inst' panel/gauge R&R.
Fuel filter appears empty ? Must be a bad fuel pump.
After their hale mary attempt at cure fell short is where their internet posts begin.
Like someone else said, dig deep enough in your own car and you will find the root of the problem. Good hunting.