(A) Lower optical train showing prism box, spacers, and lower periscope.
Drill a 3/16" hole in two of the Prism Box Standoff Spacers so that an allen wrench can be inserted through the holes to tighten the screws which lock the Light Lever Pickoff Tubes in place.
(A) Lower optical train showing prism box, spacers, and lower periscope. | 
(B) Remove the position detector lower periscope.
Note that the Light-Lever-Standoff-Spacer is asymmetric and that it is installed so the 5/16" hole for the periscope is closer to the Prism Box than to the Optical Rail.
This section will be covered with tape to protect the optics from dirt and splashed buffer.
(B) Remove the position detector lower periscope. | 
(C) Wrap with 1" black tape (Thorlabs T137-1.0) and cut two holes with scalpel (see description).
Larger hole is for the lower periscope, and the smaller hole is for the wrench to access the screw in the pick-off assembly for adjustment.
(C) Wrap with 1" black tape (Thorlabs T137-1.0) and cut two holes with scalpel (see description). | 
(D) Reinstall position detector lower periscope.
(D) Reinstall position detector lower periscope. |
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