Looking good Justin
I wouldn't spend any time worrying about head gaskets, I've seen a lot worse looking EGRs with no damage.
Just wondering: you have a programmer, but I haven't seen you post what your oil vs coolant temperature differentials are. IMHO, that number really tells you what the condition of a 6.0 liter is, after that it's judging how plugged your oil cooler is. If you're willing to do the coolant change/chemical flush/"correct coolant install" I think the 6 liters can run forever without studs or even worries of head gaskets.
I've got four buddies who've been to battle with the 6.0 liter, and I would say this: every issue could have been fixed if Navistar would have simply stepped up and admitted they had a coupleof problems early on. Fix all of the factory flaws and keep an eye on your tuner.
And by the way: great looking rig