The two bungee cords will eventually end up as 8 total pieces. Pick the right size crimp terminal rings: The crimp ends should be just large enough for the bungee cord to fit through, and the screws that hold the lugs onto the shell should fit through the rings. Prepare the shock mounting system using the bungee cords, the crimp-on ring terminals, and the hose clamp.

Pliers, tweezers, or other soldering aids.

short microphone stand (another second hand store find).

metal container to hold and shield transformer, and mounting hardware.

1:1 ratio audio isolation transformer (pulled from a second hand 270-054 I got for $1).

Resistors: 100k ohm, two 10k ohm, 10 ohm.

100 ohm potentiometer, also called a variable resistor.

A six-pole four-throw rotary switch (I scrounged my switch from a 4-way printer 'data' switch box), or you can use Mouser part no.

Two 1/4' TS (mono) female phone jacks (at least one needs a tab for a normalling connection).

Male XLR 3pin panel mount connector and mounting screws.

Female mounting flange for 3/8' microphone stand and small bolts to mount it.

This was about $1.50 at the hardware store.

Adjustable hose clamp (the same diameter as the magnet of your speaker).

Two miniature bungee or elastic cords.

I found this one for $2 at a second hand store. Cheap is okay, but you'll want something with lugs that screw into the shell, not springs or T-rods that screw into couplers. I pulled this one from an Altec Lansing multimedia system that had a blown amplifier.

Use speaker as microphone