Power steering line confusion?!?

[txhookem]

Was hoping someone could help me out with this. I need to replace some of my power steering hoses due to leakage on my '02 3.9. I need two hoses:
--High Pressure Line From Rack to Cooler
--Low Pressure Line from Cooler to Reservior

My repair shop quoted me $900. Not that I can't afford it, I would just prefer not to pay it and I have some time off next week, so I figured why not try to fix it myself.

Anyone with experience care to throw me a bone? Like how tough of a job this is. I've already replaced the pressure switch myself. I posted in another thread, but got no response.
Should I just replace all of the hoses since I'm going to be doing this? I understand there are 4. I copied these parts from the other thread:

power steering pressure lower hose (3F524)
power steering pressure hose (3E576)
power steering reservoir pump hose (3E525)
power steering return hose (3A713)

Can I get these at O'Reilly or Autozone? Do I have to get them from the dealer? I have no idea on how to look these up other than google. I found them on a site called YOYO part.

Last question is if I should only replace the two hoses that need it, then which ones are they exactly.

 

[joegr]

...
--High Pressure Line From Rack to Cooler
...

No such animal.

Reservoir
-
Suction (low pressure) hose
-
Pump
-
High pressure hose
-
Rack
-
Low pressure hose
-
Cooler
-
Low pressure hose
-
Reservoir

The only high pressure hose is the one between the pump and the rack. The high pressure hose has fittings at each end (and may have a pressure sensor in the middle). The low pressure hoses use clamps.

 

[txhookem]

I ordered these hoses and the coupling from O'Reilly. Could you tell me if this seems right?

Hayden - Steering Cooler Coupling: 250 1 Ship $4.99
Hayden - Steering Oil Cooler Hose: 105 2 Ship $29.98
MasterPro Power Steering Hose - Pressure Line Assembly: 80598 1 Ship $22.99
MasterPro Power Steering Hose - Pressure Line Assembly: 92113 1 Ship $38.99