OK then... well to address my comment about the 7.3 PSD, Ford/Navistar realized that wasn't the ideal setup and went with a VGT turbo on the subsequent 6.0 PSD. They made up for the increased boost at low RPM (and thus increased fuel consumption) by making the engine itself smaller and more efficient.
This turbo stuff isn't quite as straightforward as putting together a combo for a typical Mopar gas V8. My comments aren't intended to be "be-all-end-all" answers to anyone's questions just things to think about because it's a very complicated subject. Having early boost isn't a "bad" idea it's just not exactly optimal, in my mind because low RPM is where gas engines are most likely to encounter knock and the last thing you want to do is load a gas engine down hard at low RPM and hit it with a bunch of boost.
Case in point the Ford "Eco"Boost engines in the trucks. People get worse gas mileage towing with those than with the N/A 5.0L V8 because the engine is simply too small for the load and the AFR needs to go super rich to keep the engine from melting down.
Again, saying this more for everyone to gain something useful (hopefully) not really directed specifically at you.