Install isn't hard at all. You can drain the coolant and then do it, or if you just don't mind getting soaked then all you have to do is locate a 12mm allen head 3/8 drive socket (1/2 would be nice) and there is a thread in thing under the intake manifold that is extremely tight in there. Best thing to do is get some penetrating chemical such as PB Blaster and let it soak into the threads for a bit.
I'm not sure how hard it is with the stock intake manifold, because I am running an o2 induction clone and all of that is out of the way for me. Might be easiest if you remove the intake manifold...