3 is the overflow
2 is the fitting for a hose to the carb
1 is a restricted (probably) fitting for a smaller hose to a fuel pressure sender.
Out of sight behind the pump should be a threaded (not pipe thread) hole for the inlet fuel hose fitting.
This is the fitting needed for the inlet - note it uses an O-ring to seal -
If you are basing your guesses by the direction the fitting face - No problem, the rt angle fitting should have a stop nut against the pump, loosen this and rotate the fitting as needed.