Nothing special that needs to be done. The AD injectors found in the 99.5-03 7.3L's flows a bit more than the AB's from the early 99's. But they are interchangeable without any mods.
Just yank the old ones out, and remove the glow plugs. Make sure you have new o-rings on the new injectors, coat them in oil, and install. Use a rubber mallet to seat them fully. Once the injectors are in (and glow plugs still out), loosely slap on the valve covers, and unplug the CPS (or leave the injector wiring harness unplugged), and rock the key a few times, then do extended cranking to evacuate the cylinders. Reinstall the glow plugs, button everything back up, and take it out for a test drive. It's going to smoke for about 30 miles worth of driving, then it will clear up.
