Leica EM ACE600 Operating Manual page 20

Take the back plate of the shielding out of the packaging (3 flat sheets).
1 2
3
The three plates fit together in the rear of the coater like as shown here:
The first shield goes into the right top corner of the rear of the coating chamber.
Align hole to the pin on the chamber wall and push on.
1
Operating Manual Leica EM ACE600 Version 06/15 Page 16