I have replaced a leaking fuel regualtor on the Jeep (fuel injection)
But I can't get it to seal. Am I doing something wrong?
It squirts out where it attaches to the fuel rail.

Have You Changed The O-ring On The Fuel Pressure Regulator?

The pressure regulator came with new O ring
I'm thinking (here's trouble) that there are different models and the fit is just not right. They look identical but I can't judge by looks

if you didnt put some kind of oil on the o-ring you might have damaged it when you installed it on the rail.