85mm f/1.8

Step 0: Requirements

Lens, Triple zero Phillips, Plastics Prytool (Or equivalent)

Step 1: Remove the screws

Remove the three screws outlined in the image.

Step 2: Remove the retaining ring

Note the image from the 28mm F/2.8 guide. It will look the same.
Gently circle around the ring, prying it up a small amount. These parts are not needed for the conversion kit, but if you would like to put them back together, proceed cautiously.

Step 3: Remove Aperture Control Interface

Note the image from the 80-200mm f/4 guide. It will look the same.
Pull up with an orthodontal twisting motion, as this piece is under spring tension.

Step 4: Remove three screws

Remove the four screws and keep them safe for reinstallation. Note that the image depicts three screws; however, the 85mm f/1.8 lens has four screws.

Step 5: Remove Inner Aperture Control Ring

Note the image from the 28mm F/2.8 guide. It will look the same.
Carefully remove the inner aperture control ring. This part can be difficult to remove. Ensure to apply even pressure upwards away from the lens. Tilting it may cause damage to this part. These components are not required for the conversion kit, but if you wish to reassemble them, proceed with caution.

Step 5.1: Image of the inner aperture ring.

This is a zoomed picture of the inner aperture ring.

Step 6: Remove the outer aperture control ring

Remove the outer aperture control ring.

Step 6.1: Cautioned small parts

Pay attention to the automatic lock and aperture click detent They are friction fit And can be easily lost .!

Step 7: Remove screws for aperture control click

Remove these two screws for the aperture control click.

Step 7.1: Remove screws for aperture control click

After removal of the click control

Reassembly of the lens

Step 8: Install gear aperture ring

Put the gear aperture ring on the lens. Ensure it fits properly without forcing it, aligning it with the middle peg on the iris.

Step 8.1: Use the D key

Install the D key in the aperture control ring. The letter should face upwards, away from the lens. Align it between the two prongs of the lens aperture control ring.

Step 9: Install EF lens mount

Note: The animated image is from the 50mm f/1.8 guide and will look similar.
Align the screws as indicated in the GIF. The silver screw goes in the spot labeled as 'odd'. All four screws should be installed.

Step 9.1: Attach EF Lens Mount

If the holes do not line up, rotate the lens mount 60 degrees or until the next hole aligns. Not all hole spacings are the same. There is only one correct way that this fits on.

Step 10: Assembly complete

Assembly is complete.