There is no such thing as "liking forced induction" Every engine will make more power with positive atmosphere. Prochargers version is making around 630hp at 7-8 psi, this is a conservative tune on an otherwise stock engine.
The 7.3l seems like a pretty good candidate, the obvious hurdles are:
Its a single cam engine, sensors and logic don't match the 6.2l at all. This means there isn't a lot of hope of controlling it with the stock engine management system. If your truck is caveman bare bones this isn't a huge deal because the integration of the 7.3l control pack (supposedly forthcoming from ford) would be fairly straight forward. However if your truck has all the bells and whistles the integration is going to be difficult. The early trucks that have minimum traction control and lack the multi terrain modes and advanced sync integration will be much easier than the later gen 1.
No one has done it yet, being the first is an expensive proposition.
Pros:
The 7.3l is lighter.
It will essentially bolt in, uses the same engine mounts, same trans pattern. It is slightly longer, but narrower... more room for turbos.
There is already more aftermarket support for this engine than there is for the 6.2l.
6 bolt mains from the factory, heavily reinforced block, forged crank, deep skirted block.
Rods/pistons are not factory forged, of course neither are the LS platform. With the rigidity of the block these will make good power on FI applications without need of tearing into the bottom end.
Basic mods and tuning push this engine over 600hp, that's supercharger territory for a 6.2l.
The cylinder heads are very good, room for plenty of lift, early ported forms are flowing 395 cfm. This means around 800 HP NA is possible. There is already a build at 790hp, and it is destined for a 3 liter whipple, if it was running more compression it would be over 800.
It's already being embraced by numerous tuning shops and swappers, aftermarket support already exists and the engines haven't even started to populate junkyards.
Saying the 6.2l is superior to the 7.3l is a bit like saying the 5.4 is superior to the 6.2l. The 7.3l is more displacement, more head flow, 2 generations newer engine management.
I hope this will be a someday project for me. 2-3 years from now these engines will be available from low-mile totaled trucks for a few grand. Right now with crate engines being the only option, and the aftermarket still being in fledgling state it will be difficult to accomplish. I have no doubt we will see these migrating into newer and newer vehicles, and then its just a matter of someone doing it.
Yes it's rated at 430hp from the factory, only 19 more than the raptor. Its also rated at 475 ft-lbs, 42 more than the raptor, but look at the curves: average torque is way up. Its at that power level with NO power enrichment, and a truck tune for low grade fuel and heavy loads. Tuning produces 60 ft lbs under the curve and 50hp, more if your willing to switch to premium fuel. And remember, this is on a heavy duty truck cam.
Ford intentionally neutered the tuning on these engines. It makes the EPA happy, and more importantly keeps the diesel on top of the heap for horsepower. The 7.3l is a $2,045 option, the diesel is $10,495, they are not going to usurp it.
The sad fact is no one is swapping engines in gen 1's. Its a tough pill to swallow on an inherently special, and valuable vehicle.
