With your current setup, the cost of going EFI to carb would not be worth the very modest performance gain you would see. I can't even believe you'd consider going this route with your car
The aftermarket is absolutely flooded with GREAT parts for EFI 302-based motors. Now, if you are thinking about a HOT 351W-based motor (either nat. asp. or w/ n2o), then going the carb route makes MUCH more sense.