Fuel injection?

I am preparing to redo a '72 Duster. My question tonight concerns the various engine options I can look at. Specifically, I would like to put a newer fuel injected 3.9 V6, or 318. Is there any company which offers a "brain" for this swap? I am not interested in trying to bring all the different sensors over, just a computer which would control the fuel injection. Is there something like this on the market, or is my only choice to get an older engine and go with a retrofit fuel injection package? My goal is to end up with a nice reliable fuel efficient daily driver.
Thanks,
Cal