Right, for anyone who needs to know.
The fuel lines easily come apart. They are clipped togetherand are designed to be unclipped, with a release button on the female side of the joints. There are joints just infront of the fuel tank that are ideal to split with the back of the car lifted up and a container underneath.
I used the lift pump in the tank to pump the fuel out. Access gained under the back seat. Electrical connector has four conections. The two outer are the pump and the terminal fed by the brown wire is earth.
Connected 12V to the outer terminals and pumped all fuel out of the tank via the disconnected black 'feed' fuel line. Then reconnected the feed leaving the return disconneted. Put another gallon of diesel in the tank and again ran the lift pump to try and prime the pipes. Replaced the electrical connector and started the engine up letting it run at idle until the gallon of fuel had worked its way through and been pumped out of the still disconnected return fuel pipe.
Reconnected the return pipe, added a futher gallon of diesel and drove the car back to the filling station.
PD130 running like a dream again!
I first called the AA by the way. They could only offer to take the car to the nearest approved centre (actually the filling station I was at!) who were then going to charge me £200 for 15 mins work and fuel disposal!