Really, when it comes right down to it, you do not NEED anything other than the standard double barb inline. There is no required routing, and you can in fact, route however you would like. As long as each injector can return fuel to the tank, the hoses can go wherever the heck you want them to, and a dead end cap can be simulated with a rubber plug and a clamp, and T's in the line can be done with standard plastic barbed T's and not fancy 3 barbed return line caps. Call me a spoil sport, but spending more time CNC'ing fancy variations is not needed, unless you just really enjoy doing that!
This is the part of my job that I really enjoy! I like looking at things and seeing how I can improve them and or make something work better. I also like the challenge. Most of what i do at work is look at the print and make the part put it on the skid and move on to the next part, but when I make things for my self I get to engineer it figure it all out then I actually get to put it together test it out and see how it works. Some times good some times not so good but when you make something and it works out well its a very gratifying feeling knowing that I made that.
If you think this little project is over kill you should see some of the other stuff I have made.