Dear K. Wi, regarding process screw we have one details maybe to add: when many screws screw the same piece operator has to verify that the connector is balanced.
We had one defect Faiveley, operator put two screws by hand and screw torque one screw then screw torque 2nd screw. Problem is second screw cannot screw completely because connector cap is inclined.
Please see more details with K. Ball.