Yeah, that's too short in my opinion. Has this guy done the 6.4 before?
I'd run Ford OEM headgaskets, ARP studs, and have him go ahead and remove the EGR brackets if they're still on there.
You'll also have to have the heads inspected. You don't want to put cracked or warped heads back on after you just paid money to have the studs done. You'll end up having to have it done again probably.
Also, hot tank that intake while it's off. The EGR leaves a bunch of soot and oil in there. I'd probably do a full coolant change too. These are all things that could be done at one time and you'd be good to go.
He says that he's done dozens & dozens of 6.4s and can practically take the cab off and put it back on in his sleep.
I took the EGR cooler brackets off when I did the delete last weekend.
He did say that he would magna-flux the heads.
My truck has 47K miles on it and I've been running the Spartan 250 tune that "turns-off" the EGR, except at idle, where it cycles the EGR valve. I did the DPF delete & tune the day after I drove the truck home from the dealership (bought it brand new). Much to my surprise, when I removed the EGR valve & housing assembly last weekend to install a Flo-Pro elbow, it only had a light coat of soot on the inside, about as thick as a light coat of black spray paint.
After doing the EGR delete, I drained the coolant, flushed the system multiple times (drained through pet-****, lower radiator hose connection & driver's side block drain), ran Restore thru the system for 90 minutes @ 194 degrees, flushed it another 1/2 dozen times, ran Restore Plus for 90 minutes @ 194 degrees, flushed it at least a dozen times, flushed it 3 times with distilled water, replaced the thermostats & gasket, replaced my radiator hose o-rings and refilled with CAT EL-1 "red" concentrate, then topped off with distilled water.