As martysmartie said have you checked the earths , if your getting 8V you know its working albeit a bit low . The information you have put is a bit lacking in terms of fuel pressure etc , have you tried to start the car at all? The prime will only be a short period and yes the O.E fuel relay feeds the amal valve and idle valve aswell as the pump. It should work fine using the oe setup to trigger your new relay. If not then check it all and the earths .
I was going to try a completely seperate fuel loom. Using the o.e ecu relay(l6) to feed iscv and amal instead of the o.e fuel relay . Does anyone know if thats ok ? sorry to hijack the thread but it just seems worth asking as OP may want the same, iirc i,ve seen it mentioned before on here but cant find thread