Stupid, but i'm confused ... can anyone let me know which is the inlet, outlet and whatever the 3rd one is for?? I searched but see no answer...diagram *suggests* that the middle may the the the outlet, but anyone know off hand??

Dug this up on another site:

They are "D" (pressure - to engine), "S" (intake - from fuel tank, large outlet), "R" (return - to fuel tank, small tube). If "S" and "R" are reversed the pump will suck unfiltered fuel and rust or other material can easily contaminate the injectors or even jam the close tolerance pump!

Going down to check and see if they're marked.