Shawn, with due respect to you and David, I wouldn't try to convert a return type fuel system to be returnless, by simply capping off the return at the fuel rail.
At best, your fuel pressure is going to be way higher than it should be, which will cause the injectors to squirt way more than they should and the engine is going to run extremely rich. Not to mention having one very confused ECU that will not be able to figure out what's going on, and will probably go into limp mode. You'll also probably burn your fuel pump up shortly, as it won't appreciate pumping "dead headed", with no outlet other than the injectors.
The simplest returnless systems are not "truly" returnless because they simply relocate the FPR at the pump, inside the tank, and they just run the output of the pump at the required 43 PSI, and return the rest directly in the tank. This isn't as good as having a manifold reference line running to the FPR that keeps the deltaP across the injectors at 43 psi, instead of just the fuel rail at 43 psi, but you might get away with it for an engine running at atmospheric. No way would this work for a boosted motor.
The fancier returnless systems incorporate some sensing electronics to control the pump output to have the correct deltaP across the injectors at all pressures (atmospheric and boosted).
If I were you, I'd figure out a way to convert the VVTi motor's returnless fuel rails to a return type, then I'd put a conventional FPR there, and hook it up the usual way. I don't think the ECU will care, and the injectors will be getting the correct pressure across them.
L O L that right there kinda just went over my head, but makes sense. I dont know much about adjusting fuel pressure, & making sure it stays right. Im glad im not having to do this on my build. I like having returnless & no egr on the vvt-i, Less stuff to have to mess with, when having to do a build like mine. Also one less thing to have to mod when i did my S&S header install.