Hey man, i hope this link may be able to help you- i tried asking several buddies and its a matter of knowing the piece when you remove it the first time. I know the the dished sides of the accumulator piston should face towards the seperator plate, i just cant picture the actual 'legs' on the piston. I suggest checking this link out it has a couple good diagrams:
Also, another thought, look at your lip seal on that 1-2, make sure it is facing the correct direction in respect to the actual piston, it needs to 'seal and slide' properly or you'll be doing yet another rebuild. Hope this helps you get the wheels turning again. Good luck.