Brit if you are going to use the pump shown you do not need the regulator 4psi is the correct pressure for carbs! the pump needs to be mounted as low as possible and close to the fuel tank! as they are a push type and not a suction type pump if you get what i mean? I have one of those fitted on mine, it is mounted on the front of the spare wheel well, it has been no bother at all! I made a blanking plate out off a sheet of aluminum You just need to remove the pump pushrod!!
I was just concerned that 4 psi was on the limit of the float valve and may leak, hence the regulator to tune it down a touch.
But if your's works without leaking then that's good.
I was thinking I could attach it maybe at the front, possibly just where the solid pipe comes along to the front of the car.
Is this line too far from the tank for this 'push' pump?
(never had a close look at the connection to the fuel tank- does it have a solid pipe connected to the tank? Did you have to cut the pipe and fit the pump there with new connections?)
What about the wiring so far away from the fusebox? You attached a positive fused wire along the fuel line to the back?
One more thing: Did you wire it up so it starts pumping on the ignition switch ON before you turn it to the starter motor position if you get what I mean. So it fills the fuel lines before the starter motor is initiated.