Release the vise-grips and remove the piano wire, there should now be a nice coil to hold the filament.
Take a piece of pencil lead and place it in the coil. It will be quite loose.
Using the needle-nose pliers, gently adjust the coil so that it tightly holds the pencil lead. Only make small adjustments at a time.
Cut any extra length off the end of the coil.
Repeat for the second wire.
Bend the two wires such that they will hold the pencil lead vertically in the center and so the long leads align with the holes in the lid.