Looking for fuel pump/pressure regulator advice

If you have too much fuel pressure the fuel should be overpowering the floats in the carb if that is the source of the rich condition. You would see fuel dribbling in the throat of your carb while idling. If you have a rubber fuel, (pressure of suction side of pump) you could pinch the line to restrict the fuel pressure to the carb even to the point that it completely blocks it momentary. Very soon you would see a smoother idle and higher vacuum IF the high fuel pressure is problem, that is until the fuel level in the carb drops way to low and the engine starts to stall. Many carbs will run will no problem at 8 psi but a few simple checks should get you pointed in the right direction.