Grumpy's diagrams are center target! I am a fan of two complete fuel systems from the tank forward and return-type pressure regulators. When set up properly with the correct size lines,, filters, pumps, and regulators, there is never a doubt as to whether you are going to get the right amount of fuel when you need it.
For my main fuel system, I use an Aeromotive Eliminator fuel pump with an Aeromotive fuel pump speed controller with -12 lines to the pump, -10 lines to the fuel rails, then to the return-type regulator and -10 return lines. I use the speed controller to keep the pump at a low ebb as I drive my car on the street as well as the track. You won't need anything with this much flow and pressure, but the setup can be the same configuration.
For my nitrous system, I use a Walbro in-line with -6 lines to the return-type regulator and -4 from regulator to the solenoid.
Although I have an abundance of potential fuel flow and pressure with just the Eliminator system, I run two systems because my main pressure regulator is controlled by engine vacuum or boost, therefore, the fuel pressure varies and I need steady state 55-60 lbs of fuel pressure under all conditions, which I can set up with the secondary system. It is critical that you set your fuel pressures while flowing as opposed to static, otherwise, you won't know if you have a pressure drop when you kick the solenoid and can't compensate for it. Most nitrous systems I am familiar with are jetted for a certain fuel pressure, so the correct steady state pressure saves a lot of aggravation and broken engine parts.
All the fuel pressure and flow numbers will depend on what kind of a nitrous system you are using...for instance, I use a couple of NX Shark nozzles in a two-stage set-up so I need between 55 and 60 lbs of fuel pressure at the solenoids. You don't need anywhere near that if I understand what your system is, however, I find the configuration I use is conducive to safe nitrous use under all conditions.
Hope this helps the cause.
Wayne