Success!
I checked a few things this morning and finally decided that my problem was not electrical. So I gently straightened the needle on the meter, re-adjusted the coils and all is well.
Now to put it back in the car, make sure that I have good earths on both the meter and the sender, and see what it says.
I am fairly sure that the float is OK but I will just pop it in some warm water before I put it back in the tank. Fingers crossed.
Roger
Roger Grix