It seems that it is fairly easy to fit a flow meter to petrol engines but all the ones i can find say cannot be used with diesel, is there such a thing for diesel?
If your engine is less than about 200hp I have a used Mecdine unit for diesel engines at a fraction of the price of the other two mentioned. Also makes the engine self bleeding and cools the fuel. Fairly straight forward to fit.
Cheers,
Peter