I image they want egr delete/studs. My 6 leaker I used to have had the cab off a couple times. I had 225cc injectors and a large non VGT whirlybird as well tho lol.What are you referring to as bulletproofing? Head studs and bulletproof egr cooler? Also replacement of oil cooler and updated fuel pressure regulator kit? What year 6.0 ? Early models such as 03-04 models also recommend new HP oil pump , as the smaller early pumps are fragile. when cab off 6.0 repair is being performed you must also consider a complete engine reseal to repair oil leaks from the bed plate and rear cover and front cover. Really fix all the issues the 14-18 year old engine may need. Also need to consider how much crankcase pressure/blowby engine has.
Mine is an 06 with 265k, last time I checked little to no blowby, uses only about a quart every 3k if pulling heavy load.
Looking for studs, egr delete, probably oil cooler, possibly injectors, etc.