Man, I miss my 240sx

Still doesn't change the fact he would be much better off trading up.

Now, if the X is a second vehicle that can be a dedicated project car (that he won't mind totally writing off if he can't get the conversion to work), and he doesn't mind doing all the work himself, and doesn't mind having to figure out significant parts of a conversion - from plumbing, intake manifolds, exhaust manifolds, Fuel and air management, etc. all by himself - then he should go ahead and knock himself out. Doing things for the thrill of doing them is part of what makes like interesting.

But that isn't what he asked. His first question - "Is it worth it?" can best be answered by a resounding no - esp. given the context that in the next sentence he notes all the bolt-on stuff is for the V6.

Power is neither fast, easy or cheap. Factory power is the easiest and cheapest. Normally aspirated factory power is the best of all - and that is what the '05 and '06 deliver in spades. Can't afford that? Then the Supercharged V6, followed by the normally aspirated V6 are your next best bets. Unfortunately for him, the 4 cylinder is way on the bottom of the heap - esp. with a vehicle that weighs as much as the Xterra does. Turboing a KA is no easy feat, even when it's in a vehicle like the 240 where there are others doing it. Why do you think the SR20DET swap is so popular on 240's? It's way easier.

Now an SR Xterra - that would be interesting. Except the KA has more torque, which is more valuable in a truck.

Anyway, he can do what he want's - I wish him luck, but really if you ask if something is a bad idea and then everyone confirms that it is, you shouldn't be surprised