The thread pitch is the same as any ford modular motor (aka 4.6 and 5.4) I got mine right in the exhaust section of a parts store. I studs are a little longer, so in some spots its too long, but for the rear spot its perfect as it goes in deeper into the head, helping prevent the common stripping and exhaust leak in the rear of the exhaust manifold.

88 Montero, StarQuest turbo, Kormex 5speed +tuff-pan w/phoenix f. stage2 clutch, 4in lift+33' tires, 4.875 lsd, short-throw shifter, Aisin hubs, SR big brakes, gen2 uca's, elantra alt, and so much more... 16g turbo w/hardpipes + 4.90 locking disk-brake axle soon (maybe lsd or aussie front??)