You said that the car runs already (with the fuel line disconnected) so we know that it runs, which means there shouldn't be any ignition problems. So no need to look other places. The problem IS fuel line related in some way. We know that the pump works because he tested that. The fuel return line to the tank is the line that comes off the fuel pressure regulator and goes to the false firewall and then down under the car and back to the tank. The pass. (On LHD) side fuel line is the delivery line, make sure that line is delivering the fuel. So I would do what Steve said and make sure all the lines are hooked up correctly and then make sure the return line is not clogged and fuel can flow back to the tank. I might even put a new FPR on there while at it (especially if it was hooked up wrong).