He is upgrading injectors=more power=increased cylinder pressure=bye-bye TTY head bolts, and unfortunately yes, they just go bad when adding power. Nothing negative about studding it, please don't suggest doing studs one at a time, terrible idea, and almost guarantees failure, little more effort to do a proper head gasket job, for alot of piece of mind. Have to be diligent while doing head gaskets, check block, have a reputable machine shop check heads for cracks, deck heads, and appropriate valve work. Also while rare(even though this clearly is not the case here) check cylinders for cracks, it happens. No jab at you, I realize you have been doing this for four years, I unfortunately started in 03, and back to one at a time, just call as many reputable shops as you like and ask if they will do it, don't just take my nonsense advice as correct.
LOL!
04.5 and up. You have log style rails(03-04), so no stc worries. You got lots of good advice from this thread.