Jonas,
Relax a bit, bro. You sound like you need a beer.:chug:
The truck isn't doing anything different than it was before the gages.
There's a saying I heard off a Ford kid that applies here:
"The only people with oil temperature problems are people with oil temperature gages."
Not to diminish the importance of gages and the information they provide, but you're stressin' way too much about those numbers. That truck will run all day long at 1100+ degrees and as long as ambient air allows the coolant temps to stay in check you'll never hurt a thing. Especially with stock fuel.
I don't know from experience on the 6.7, but every previous evolution of the Cummins engine has been more temperature tolerant in regards to EGT. 5.9's will easily take bursts north of 1500 for short durations.
You wanna bug your eyes out? Go up to the drag and pulling forums, ask what those guys hit for EGT. Especially 2.6 and 2.8 non-water pulling classes. Quite a few of those are still daily drivers.
Sounds like a nice truck, man. Relax on that pyro, make sure the tip is centered in the port, and get us some pictures of that ride. $.02