OK, I know the pickups use an extra ring or spacer between the TBI unit itself, and the air cleaner. Perhaps vans did too, I don't know. But if you have raw fuel leaking past the joint between the TBI and spacer, or the spacer and air cleaner, I would think there's still an issue with the TBI or lines. Those injectors should spray in a nice even cone pattern right straight down into the the bores of the throttle body. None should be going sideways and hitting that metal ring or spacer. If it is, there's a problem.
There are seals on the TBI unit for the injectors and pressure regulator. Kits to reseal them are cheap.EBAY KIT
A quick study of some of the kits and whatnot on ebay will also give you an idea of how they come apart.EBAY SEARCH