carter carburetor

I got a carter afb carb for free from a buddy.
It has two fuel fittings, one at the bottom in the middle, and one at the top on the side. Does anyone know which one is inlet?? and is the other one a return, or vent recovery or something like that. If it is a return, can i run more fuel pressure than the carb wants or not??

My plan is to use an electric fuel pump with a return style regulator to drop fuel pressure and not burn out the pump, if my return line comes off the regulator, should the return from the carb be capped, or should
i T it in with the return from the regulator so I have a carb and regulator return that meet and go to the tank??

Thanks