There's a few little hitches here n' there, and you'll need that fancy-schmancy "quick disconnect" fuel line tool to unhook the fuel rails from the supply/return lines, plus a pretty sturdy Torx bit (T-15, I think) to take that goofy "5.0L High Output" plaque off the top of the intake plenum - the screws are a turd to take out if they've been in there since the factory, and you might have to drill the heads off a couple.
Main things:
1. Remove UPPER intake manifold (don't have to remove the lower) and all the vacuum lines, sensors, and throttle linkage stuffs hooked onto it.
2. Immediately stuff rags into holes of lower intake manifold so crap doesn't fall in, and THEN begin scraping the old gasket material off.
3. Relieve fuel pressure from fuel lines. I just put a rag over the schraeder valve off the rail and push the valve in with my fingernail or a screwdriver very slowly/gently. Then you get to wrestle with trying to make those stupid "quick" disconnect tools to work on the fuel line couplings.
4. Unplug the electrical connectors and remove the whole fuel rail assembly. The injectors usually will come off with the rail, but a few might stick in the lower manifold. If they do, just wiggle 'em out, but make sure you don't leave any o-rings in the lower manifold. Pick 'em out with a ... uhhh ... o-ring picking device. (A bent coathanger worked for me.

)
5. Stick new injectors on fuel rail in place of old crappy, leaky, ugly OEM units. Make sure everything is 1000% spotless squeaky-clean, and give the O-rings a little dab of motor oil on your finger to help 'em seal (helps things slide together nicer, too).
6. Assembly is reverse of removal ... except, like, it doesn't take as long.

Make sure you don't leave any vacuum lines disconnected (or broken/cracked), or you'll have a headache for weeks afterward trying to figure out why it's running like crap.
Enjoy!