Racer Walsh makes an adapter to bolt a 2 barrel to the EFI lower, but you will have to plug the injector bungs.
There are also some 2 barrel manifolds out there from older Mustangs that would work, and some that are made for dirt track racing. Also, Offy made a 4-barrel intake (that is no longer in production), if you can find one of those you could get a 4 barrel to 2 barrel adapter and use that.