The Plus 8 has a strange design feature, a realistically accurate fuel tank sender, but no low level fuel warning light even though the gauge has a provision for a warning light, as does the water temperature gauge.
As well as fuel and water temperature gauges there is a digital display, showing fuel in % and temperature in degrees centigrade.
When the digital read out is down to 0% the tank has 5L left of the 55L, and I can then add 50L.
But just to remind me it is a Morgan, to fill the tank takes about 5 min: the last 10L has to be dribbled in at snails pace...