Thanks for the reply Bob.
The fuel pipes on this landcruiser are the old steel ones, so you can imagine how rusty they are, there is a fuel leak coming from the return pipe very close to the fuel tank. My father has already bought the new (steel) pipes ,I couldn't believe how expensive they were but hey if you need them.....
From what I can see underneath ,the fuel tank has to come out to access the pipes , one of the bolts that hold the tank straps is so rusted that I can't even move it, I've covered it in penetrating fluid so will have another go tomorrow depending on the weather......