17 Here’s where EFI can cause some concern for some people that are undecided about it. A good EFI kit will not only have a fuel feed-line, but a return line as well. A stock gas tank usually doesn’t have a provision for a return line, but installing a return line can be done a couple of different ways. One is that a rear sump can be added to the tank (Like Ralph’s Road Runner already had), a custom tank can be built, or a factory tank can be modified and fitted for the required line attaching points. We did an Internet search and could only find aftermarket tanks with the pump already installed, so that is another option. In some cases, the factory sending unit might have a port in it that is not connected to anything and can be used for a return. Just be sure that wherever your return line goes into the tank that it isn’t dumping fuel directly on the pickup. This can cause aeration and cavitate the pump.