Instructions
Wait until after dark before you approach the gate next to the Gun Runner kiosk in front of the main factory.
Crouch in front of the gate, verify that your stealth status is "Hidden," verify that no guards are in front of the main gate, and then select the gate to pick the lock.
Complete the lock-picking minigame to open the gate. While crouching, sneak toward the main Gun Runner factory entrance, keeping a careful eye out for guards. If you spot a guard, move quickly away from him so he does not spot you.
Enter the factory and proceed to the back. If it is night, the people inside the factory will all be sleeping, so you will be able to sneak onto the factory floor without detection.
Steal the blueprints as requested by Alice, retrace your steps to exit the factory and go back through the gate. Do not stand up and run until you are past the gate; otherwise the guards will spot you and attempt to kill you.