Put a t-junction in the hos that goes to the wastegate coming off the turbo(easiest way). Alternatively T into the pipe out the back of the inlet manifold which goes to the boost compensator.
thanks heaps mate,got the gauge in an mounted sweet then thought where the f does this go, tryed searchin for some picturs but never found what i wanted. ill try an get a photo of it incase someone else might have the same problem