If it is NA the 6.5 long block will bolt in. You will just have to use all the CUCV accessories, water pump, manifolds, IP, etc. It is a bolt in- in fact the government is no longer rebuilding 6.2's, so any truck, CUCV or HMMWV, in Army service now that has a 6.2 gets a 6.5 when it gets a new...