Good job upgrading your guns, those ghouls around the abandoned apc couldn't even touch you. And since Overseer's Guardian is now non-automatic with the re-chamber to .308, go ahead and max out the rifleman perk 😉 The hidden terminal which opens up the employees area in Dry Rock Gulch should be around the section of wall between 55:15 and 55:30 behind some bushes. If you're still up to it, SCAV issue #5 is in there on the rooftop of one of the buildings. Edit: It's behind those bushes right there at 55:24.