This is a highly damped fuel level gauge matched to our standard 6-hole top-mount float-arm fuel level sensor (part number 45 003). This fuel level sensor is required to provide the gauge with the correct input resistance, which is 260 Ohms at empty to 20 Ohms full.
The gauge is supplied a 'U'-shaped fixing bracket and thumb nuts along with a 12v /2w illumination bulb. Night illumination is classic white.
The gauge size of 52mm denotes the outer diameter of the main body of the instrument and hence a 53mm to 54mm diameter hole is required in the dashboard.
The 52mm Fuel Gauge wiring diagram can be found here.