With ignition on maybe start looking for +12 volts with a multimeter in the circuits that should supply the fuel pump.
Start at the fuel pump relay where its energised by the ECU. Measure for 12 volts between the blue/purple (+ve) and white/slate (-ve) cables that run from ECU to trigger the pump relay coil. If present check also the main +12 volts from battery on the brown cable that provides supply to main contacts of both fuel pump and main engine relay. Finally you could check feed from relay to inertia switch and fuel pump, white/purple cable. Removing fuel pump relay and identifying relevant pin locations on the relay socket may be the best way to gain access to these points.
Wiring diagram
here
