I dunno. I just remember Terry informing me (correctly, I might add), that built up boost pressure on an engine was a bad sign you were over pressurizing it, as it obviously cannot flow that kind of volume at that rpm. Diesel's can, and should, take more pressure, but more pressure= more strain on parts unnecessarily, as I understand it. You also need to flow more fuel as pressures rise. It's all about efficiency, as I recall the discussion (Actually, several before he drilled it into my lil brain).
But what do I know, lol. Ask Terry. 100 PSI is INSANE to me! And I doubt intake manifold gaskets and other parts last long with that, and I cannot even imagine the exhaust gas temp readings on that engine!
But I've also heard horror stories about the 6.0 in mine, and haven't had a real problem 'cept the cold running at our recent sub-freezing (45 degree) temps of late.

129k and running strong as ever, once warmed up.
As it is, you need injectors, and this discussion is not helping that lil bro. It never ends, the cost of maintenance.
FWIW I just spent $400 fixing the g/f's Sable so it had heat because her ex-room mate put stop leak in to try and fix the leaking reservior. (what a FUN TIME THAT was, lol, asswipe clogged the new heater core! Luckily it withstood a 125 PSI pressure flush and a new blend motor).
Hence the Pontiac is free now if you need it as a loaner, lol.
Ray