All I have is a tt ecu, engine loom. Nothing else. So all I was going to do was put a tt fuel pump in, with a relay and hardwired 12v supply. So it just gets a on and off signal I'm guessing the fuel pressure regulator will look after keeping the fuel pressure correct, I imagine the stages are just to deliver more fuel at higher rpm? As the car is basically for the track. Hardwiring with no fuel should save weight and wiring complex and reduce fault finding in future.