Wattage of apw3 is not enough to support 2 antminer L3+. You will either fry the psu or won't start at all.  And you don't have enough power cables from the psu to do that in the first place.
APW5 can handle both of them but again not enough cables.  And APW5 tends to get extremely hot for some reason so I would avoid it if I were you.
Also it would cost you less to buy 2xapw3 vs 1xapw5.