Many thanks again Charles. I did consider the 100% fuel indication being compromised by a shunt resistor, but since it's sometimes difficult to achieve anyway after a fill up, thought this less important extreme of indication not worth the worry.

I'm very interested where the upper and lower display resistance values were obtained. Was it by testing your own cars system or from a manufacturers data sheet?

Richard

2018 Roadster 3.7
1966 Land Rover S2a 88
2024 Royal Enfield Guerrilla 450
1945 Guzzi Airone