PWR steering leak at the pressure line-Please help
 

I have a new aftermarket(the dealer does not carry pwr steering systems anymore) power steering pump and lines. I have a bad leak at the pressure line where the pressure fitting screws into the reservoir. It's leaking bad, and always had since the first time the engine started. I should mention that I'm using a reservoir from a 85 Crown Vic police car, could that be the problem? Other than that, I've tried several different O-rings of different sizes but no luck. Any advice is greatly appreciated. Thanks.

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Finally DONE!!
93 GT, 393 stroker w/ Edlebrock Performer heads and EFI, 30lb injectors, Dynamic Roller Mite C4, 8 pt cage, Sothside Machine bars & Sub-frames, 3.73's, '69 351W block w/SCAT crank.