Powersteering high press line probs

Hi, just a quick one- just fitting a second hand power steering pump to my 300tdi Disco, I tried for 90mins to get the high pressure feed to fit and it still wont go. Now i'm certain that all 300tdi pumps are the same, is there a trick to fitting the high pressure feed or am I doing something wrong? Ive tried it on the car, off the car with no joy, it fits straight into my old pump with no bother.

Any advice welcomed!!

Paul