I have let the needle go below E not by choice but because I was in the middle of nowhere. Turns out when I get to the gas station I still had 8 litres left! I put in 62 litres and the manual says it's a 70 litre tank. The needle was a good ways below empty too. I noticed that when my light comes on at 1/8th tank and I fill it up I still have 15 or so litres left in the tank which is quite a bit. Even 8 litres is a lot to have when your below E.
My needle doesn't seem screwed, it always behaves the same by the way.
My needle doesn't seem screwed, it always behaves the same by the way.