Happiness is a Warm Spaceship

Arrive at the Back Bays: Head north to find Captain MacRedd.

Option B: Talk to MacRedd: If you can talk your way out of a fight (or have Felix), tell MacRedd, "I'm here for some parts. Junlei sent me." He'll mention Junlei's "last sacrifices." Continue with "So can I grab that part, then?" MacRedd will demand tribute (580 Bits), or you can pass a Lie check (40), defer the payment, or fight.

Option C: Sneak Past MacRedd: West of MacRedd, find a hole in the wall. Follow the tunnel north to a door leading to stairs and a ladder. Beware of outlaws to the east. Both paths lead to a room with consoles and outlaws. Use the door (Lockpick 25) or another hole in the wall (west of the door). Sneak to the northwestern corner to find the Radiator Parts on the wall. Avoid the northern hole in the wall, as it leads to a drop-off.

Explore the Back Bays: After dealing with MacRedd, you can search the area. If you fought MacRedd, expect more enemies in side rooms. If you didn't fight, be cautious when looting as MacRedd's goons may object (though you can talk your way out of some situations).

Find Ship Decorations: You can find the Petey model ship decoration on a table by going through a door and down stairs on the western side. If caught stealing, you can pass a Lie, Intimidate, or Persuade check (25).

Locate Junlei's Engineer: In the southeastern corner of a room, you'll find Junlei's engineer in a green suit. She is fine and willing to return to work with prompting.

Retrieve Radiator Parts: Go past MacRedd, halfway down the Back Bays, and turn west to find stairs and a ladder. Both lead to a room with consoles where the Radiator Parts are on the northwestern wall.

Return to Junlei: Bring the Radiator Parts back to Junlei on the Groundbreaker's Promenade deck.

Install the Radiator Parts: Junlei will then ask you to help install them, which involves dealing with a Mantipillar infestation in the Engineering Bay. Head to the northern end of the Engineering Bay, go through a door to the east, and ride an elevator down into a large chamber with heatsinks.