On the fuel rail, at the left hand side, there is a goldy coloured regulator (i think thats what its called). It has a black pipe coming from it that runs in front of the throttle body to another thicker black pipe. I havent got a good pic on here unfortunatly.
All i did was cut it then put the t-piece in and connected the nylon gauge pipe.
This is the best pic i have.
The red is the regulator
The blue is the black pipe that most people use to connect it too, i have herd of other places but i have always gone this way.
The green is where my t-piece is.
Hope this can help?