Part 1 - The first spawn is across from Juggernog on the chair. The second location is down the stairs outside leaned against the crashed truck with boxes and barrels on the back of it. The final location is inside the flooded bunker of a shelf left of when you walk in.
Part 2 - The first spawn is in the infirmary right up the stairs into it will be two small boxes of drinks which will have the part in-between them. The second spawn is up the small ramp on the bottom of the bunkbed next to the staircase. The final spawn is up the staircase to the left of the perk machine on the debris.
Part 3 - The first spawn is in the armory area which is opposite of the infirmary and it is located on the boxes left of when you walk in. The second spawn is down the stairs hanging on a wall next to a shelf. The final spawn is on the lowest level and it is on some debris next to the Wunderfizz machine.
Craft - You can build it at the workbench in the operations bunker