Xray NT1 fuel level indicator
Xray are now selling this fuel level indicator for the NT1 fuel tank in the form of a white transparent die-cut sticker. Simply apply the sticker to the appropriate location on radio plate beside fuel tank and when the car is lifted by rear (nose to ground) the stickers will quickly show you the amount of fuel remaining. Sold in a set of 4 they display the fuel measurement in 5cl increments.
Source: Xray [teamxray.com]