Leak at rear of power steering pump?

[MAP]

I replaced my old pump about a month ago because it was leaking from everywhere... So i notice the fluid level has dropped but the top, front and side of the pump are dry but i shine a flashlight behind the pump and theres a puddle of red fluid. As far as I know the only possible leakage site at the rear is at the oil pressure sensor/switch. The new pump i got did come with an o-ring but it was not for this sensor. Since the oring on the sensor seemed ok, I installed the sensor into the new pump with the old o-ring. Do any of you guys know the part number of this o-ring? I'm thinking of replacing it and maybe installing a copper crush washer at the base of the sensor as well. Im attaching a picture of a similar pump for reference.

 

This car is frustrating. I replaced the drivers side valve cover gasket about 4 months back. It was the only item that was still leaking oil. I changed my oil yesterday and find oil leaking from the rear down the oil pan and oil in front making its way down the oil filter. The rear Im afraid may be due to the rear main seal. I replaced the front oil seal when I changed the timing belt so the front leak cant be from there.

 

Do the leaks ever end with this engine? The front leak is not coming from the oil cooler seal. I changed the orange o-ring a while back. Could it be that blow by is forcing oil out of the seals?? I recently changed the pcv valve also.

[MAP]

Have any of you guys tried the following to rebuild your power steering pump?

 

http://forums.nasioc.com/forums/showthread.php?t=2127419

 

The pump looks the same as ours. The only difference seems to that the high pressure line is connected at the side on our pumps but up top for the WRXs. Ours have the plug up top where the WRX line is attached.

 

I intalled a rebuilt pump late last year and the thing leaks more than the original leaking pump that I replaced. I figure I may as well try replacing all the seals on the original instead of gambling with another rebuild.

 

MAP