On a VP head, the hi-pres. line has a nut with male threads that go directly into the head, and the tube just pops in. So the tube is just sandwiched between the injector and the fuel line.
The CR tubes are retained by a nut into the head, and have male threads protruding that the hi-pres. line will thread onto. It has an anti-rotation key, the VP tube doesn't. The hi-pres. line will have a female thread nut to thread onto the crossover tube.
Monster Mike also makes the correct tubes. The right tubes for regular conversion lines are a little bit longer than a VP tube and a little shorter than a cr tube. Also the tubes will have more of a VP looking thread on them
X2 on the fuel, get your pump turned down about 150-200 ccs from where it's supposedly set at and it will be a mean runner. Shouldn't need that ghetto fog to make 4 digits....