Clean the hinge? What hinge? Sorry lost me.
There are two senders one behind the passenger seat under the false floor in the glove box, stand alone unit and one under the sub attached to the fuel pump.
The pump one is a pita due to limited working space but basically you have to remove both units and clean the variable resistor contacts I used contact cleaner and those ear cleaner things cotton wool on a stick
Have to be careful not to get petrol on the big O rings as they change shape if you do, I buggared one up so need to get a new one.
I've only had it 'fixed' two days so still making sure it is fixed but all seems good at the moment.
Passenger side sender gave readings of 0 - 50 when resistance was checked with a multimeter. Driver side one ran from 0-32 then jumped to 175 but then changed frequently between 70-200 without Changing position of float every second or so, after cleaning this seemed to fix the random readings and also ran 0-50.
Why there are two senders, one in each half of the tank I have no idea..... A guide will follow.