I know this is an Impreza only thread but...
I found it easier to connect the PS lines at the pump not at the rack. The pump barely fits... but it fits.
I found that I was grounding a wire that shouldn't have been grounded. It was a black ignition wire that looked like a ground...It wasn't it was a power wire. Put a hot when on wire to it and the car fired up. I also ran a direct power line from the battery to the pump with a toggle switch...seems to work for me I was having problems getting the Fuel pump relay to work.
The firing order if your looking at the engine from the radiator its front left (1) then to the back right (6) then to middle left (3) to front right (2) then back left (5) to middle right (4).
Hope that helps good luck!