Fuel hose AN6 or AN8

That is how all the newer fuel injection cars are set up, regulator in the return line.

Well......sorta. Most of the newer GM products have a fuel filter/regulator unit. Has one inlet and two outlets. One outlet going to the engine and the other is an orificed return going back to the tank. That's what pretty much all of the modern aftermarket fuel systems are going to. I've built a few of them recently myself. It's a nice setup.