1.
2. One stick works for both cups, break stick in half:
3. Roll out a 1/2 stick to where it fits on inner channel like shown below:
4. Break segment off that is little less than 2 ribs of the channel. Will need to have it a little longer than the rib walls so it can seal against them.
5. Roll the piece broken off so it will attach to both ends of the original thicker segment that was rolled out:
6. Press it down and flatten to where it's sticking just above the channel by about a millimeter or so, and push the overhanging ends flush against the surface of the two ribs to seal. Make sure to keep the two rear peg hole clear of the putty:
7. Alternate view:
8. Press on pads at the corners, then work front to rear to press a finger inside pad on the plastic pad plate and press it hard into the cup/grille to seal pads to the housing. Keep working around the inside perimeter until you have it seated as far as it will go, then flatten the oozed seam against the inside perimeter wall with a finger. Hard to get a picture of this, but basically if you can see the putty below then your finger will go above it and under the pad and firmly press down towards the outside...just take your time and use care as you go around the perimeter, no need to rush.
9. Repeat for other side to complete.... then you're finished.