pressure to drop on Carter electr. fuel pump

Surely that car had the carbon can originally. Look under the car where the fuel line is near the tank and see if there are some smaller tubes also running front/ rear to the tank.

If you have a regulator with no bypass, the only way it can regulate is to shut off the pump head. This makes the rotor cavitate and bubble up the fuel. IT MAY in this condition add to vapor lock problems. A "bypass" regulator, which of course always feeds "overage" back to the tank, alleviates this condition somewhat and keeps the fuel a little cooler because it is always recirculating