Come Fly With Me - Exorcising the Demons
Talk to Jason Bright to learn about his little cult. Bright wants to fly away, but his little party was just crashed by a bunch of Nightkin (They're using stealth boys, so he thinks that they're invisible demons). He doesn't have the manpower to actually drive them back, so he wants you to clear out the basement.
Nightkin are a royal pain and an absolute nightmare in these close quarters. If they can manage to close the gap between you, then expect to take a lot of damage from their rebar swords. If you're having trouble with this quest, then go back and pick up Boone. Read this guide on "One for My Baby" to learn how. Once you have Boone in your group, the Repconn Basement gets a lot easier. He should be able to take out a few Nightkin on his own. As a general rule, get close and use something with a lot of penetrating power. At early levels, a .357 revolver or Cowboy Repeater should be alright. Even a Caravan Shotgun to the face should stumble them a bit.
Note that you do have some options. If you want, you don't actually have to fight more than the first few Nightkin. Look for the short dead end hallway near the entrance. If you should find a large room with a bunch of dead Nightkin and a ghoul sniper above you. Harland has been holed up in here for a few days and wants to get out. He'll only leave if you can find out what happened to his girlfriend.
There's a bit of a conflict though. You can look in the room next to Harland to find a named and peaceful Nightkin, called Davidson. He may be slipping into insanity, but he can hold it together long enough to talk to you. Just don't bump Antlers, move Antlers or make fun of Antlers. That will make Davidson hostile.
Davidson just attacked the Repconn facility to get a shipment of stealth boys so his men could remain hidden. If you want to help them out, you need to examine Harland sniper perch for records of the shipment. He won't let you come up though and it's impossible to sneak past him.
It is possible to satisfy both of their needs if you are stealthy or use a stealth boy. Davidson seems to turn hostile if you kill the Nightkin Jailer (or it may just be that the jailer is the last of his men, if you clear the basement normally). You can sneak around the jailer, and get a spare jail key from a desk. You can then use it to open the marked door in the reactor area to find a dead ghoul. Harland's friend is already dead. You can report this news to Harland to convince him to make a run for it. He'll abandon his platform. You can then go up (watch for traps on the floor) and check the computer near his post to learn that the stealth boys were sent back quickly after being received. If the jailer is still alive, you can tell this to Davidson and he'll abandon the Repconn facility.
There's no real bonus to pulling it off this way though. If you want to support Davidson, just shoot Harland and break into his post. If you want to support Harland and kill the Nightkin, just clear the area out and kill Davidson.